Abstract:
A motor vehicle seat. The seat has a seat frame; a seat back pivotally mounted on the seat frame and which can be tilted forward out of its position of use and toward a seat surface of the seat frame; a longitudinal guide with which the seat frame is displaceable in the longitudinal direction of the seat in order to adjust the longitudinal position of the seat; a fixing device for fixing the seat frame in a previously adjusted longitudinal position of the seat, an actuating element for releasing the fixing device thereby enabling the seat frame to be displaced in the longitudinal direction of the seat, a coupling mechanism, which acts upon the actuating element and releases the fixing device when the seat back is tilted forward toward the seat surface, and a memory device by means of which the seat frame can be automatically held in a preset longitudinal position of the seat, which is defined as a memory position.

Description:
REFERENCE TO RELATED APPLICATION(S) 
   This application is a National Phase Patent Application of International Application Number PCT/DE02/01908, filed on May 22, 2002, which claims priority of German Patent Application Number 101 27 151.4, filed on May 25, 2001, and German Patent Application Number 101 27 152.2, filed on May 25, 2001. 
   BACKGROUND 
   The invention relates to a motor vehicle seat. 
   The motor vehicle seat comprises, for example, a seat frame, a seat surface provided on the seat frame, and a backrest which is mounted pivotally on the seat frame and which can be tilted forwards towards the seat surface. 
   Seats of this kind are used as front seats in motor vehicles where folding the backrest forwards makes it easier for a passenger to enter the back of the vehicle or to place objects in the back of the vehicle. An additional easy entry function which is particularly of importance in two-door vehicles, is achieved if the seat can be moved forwards after folding the backrest forwards. For this purpose, the vehicle seat has the following:
         a longitudinal guide with which the seat frame can be moved to adjust the longitudinal position of the seat in the longitudinal direction of the seat;   a fixing device for locking the seat frame in a previously set longitudinal position;   an actuating element for releasing the fixing device so that the seat frame can be moved in the longitudinal direction of the seat;   a coupling mechanism for coupling the fixing device to, the backrest which acts on the actuating element and thereby releases the fixing device when the seat back has been tilted forwards to the seat surface;   a memory device with which the seat frame on moving in the seat longitudinal direction can be stopped automatically in a predeterminable seat longitudinal position defined as the memory position whereby a stop which is associated with the seat frame and which can be moved in the seat longitudinal direction moves into engagement with a counter stop of the memory device;   an adjusting device of the memory device with which the memory position is setable by sliding the position of the counter stop in the seat longitudinal direction;   a locking device for the memory device for locking a set memory position and   a switch device by which the locking device is releasable in order to adjust the memory position.       

   A seat of this kind known from WO 00/55002 (see corresponding U.S. Pat. No. 6,631,952) on the one hand provides the possibility of, after tilting the back rest forwards towards the seat surface, sliding the seat frame and thus the entire vehicle seat forwards to enable the passenger to climb into the back (easy-entry function). At the same time the seat can then be moved very simply again into its original seat longitudinal position if this longitudinal position is stored as the memory position by means of the memory device provided for this purpose. In this case when sliding back the seat the seat frame is automatically stopped in the memory position whereby a stop associated with the seat frame interacts with a counter stop of the memory device. 
   By “useful position” of the seat back is meant herein to be a position in which the seat back has an incline relative to the substantially horizontal seat surface which enables the back of a person on the seat to be supported. To implement the easy entry function the seat has to be tilted forwards from such useful position towards the seat surface. 
   The term “seat frame” herein means all the elements of the seat which can be moved by means of the longitudinal guide in the seat longitudinal direction, and thus also the parts of the longitudinal guide itself which can be moved in the longitudinal direction of the seat. 
   SUMMARY 
   An object of the invention is therefore to improve a vehicle seat of the type mentioned at the beginning, and more particularly in respect to reliably storing the actual seat position as a memory position when folding the seat back forwards and as regards subsequently arriving at the stored memory position when the backrest is located in its useful position, thus raised up. 
   The backrest is coupled to the fixing device on one side and to the locking device on the other side, so that when tilting the backrest towards the seat surface first by means of the locking device the actual seat longitudinal position is locked as the memory position and only then is the fixing device released. 
   It is hereby ensured that when implementing the easy-entry function a movement of the seat frame in the seat longitudinal direction from the actual seat position is only possible after the actual seat position has previously been stored as the memory position. 
   In a preferred embodiment of the invention, the coupling mechanism, which acts on the actuating element and releases the fixing device when the backrest is folded forwards towards the seat surface, as well as the means through which the locking device is coupled to the backrest, form a multi-stage acting loading and release kinematic unit which acts on one side on the fixing device and on the other side on the locking device in order to actuate same in at least two stages. Thereby, in a first stage, the actual seat longitudinal position is locked as a memory position by means of the locking device, and in a second stage, the fixing device can be released. 
   According to a variation of the invention, the coupling mechanism only acts on the actuating element in order to release the fixing device after the actual seat longitudinal position has been locked as a memory position by means of the locking device. 
   According to another variation of the invention, the coupling mechanism acts already on the actuating element in order to release the fixing device before the actual seat longitudinal position has been locked as a memory position by means of the locking device, and the release of the fixing device is only active after the actual seat longitudinal position has been locked as a memory position by means of the locking device. 
   The invention provides an arrangement for actuating the memory device by means of which first the actual seat longitudinal position can be locked as memory position before the fixing device of the seat longitudinal guide is then released. According to this, a follower is provided which is mounted to be movable (preferably on the seat frame) and which, with the backrest located in the useful position, is held by a locking element in a position in which it—in the memory position of the seat or seat frame—acts on the memory device so that with an adjustment of the seat longitudinal position the memory position can be adjusted together with the seat frame whereby the follower is preferably coupled to a resetting spring which lifts the follower from the memory device when the backrest is tilted forwards. 
   The follower when acting on the memory device releases its locking device and further enables resetting of the memory position when moving the seat. 
   In order to allow the follower to lift from the memory device when the backrest is tilted forwards, the locking element when folding the backrest forwards releases the follower by lifting off away from the follower. The memory device and its locking device can then move into the locked state so that when tilting the backrest forward, with the aim of implementing the easy-entry function, the actual seat position is automatically stored by means of the memory device. 
   This arrangement enables, on the one hand, a very compact construction of the structural groups provided for providing an easy-entry function, as will be apparent from the description below of embodiments in connection with the drawings. On the other hand, it can be ensured in simple manner that when approaching the memory position—depending on requirements—the seat is stopped selectively in the memory position or moves over the memory position and sets this again at the same time. 
   In a preferred embodiment of the invention, when the backrest is tilted forwards, the follower lifts away from the memory device before the fixing device of the seat longitudinal guide coupled to the backrest is released. It is hereby ensured that the actual seat position is stored by means of the memory device before the seat longitudinal adjustment can start after release of the fixing device. 
   This is achieved, in particular, in that when folding the backrest forwards about a first angle from its useful position, the follower is lifted from the memory device, and that when tilting the backrest further forwards the fixing device is released. The absolute value of the aforementioned angle thereby depends on which incline the backrest has previously in the useful position. Alternatively, the two angles can also be defined relative to the vertical (i.e. to the vertically aligned backrest). Decisive in each case is that the angle about which the backrest has to be pivoted when folding forwards until the fixing device is released is absolutely greater than the angle about which the backrest has to be folded forwards as a whole until the follower lifts from the memory device. 
   According to one embodiment of the invention, the locking element is elastically pretensioned towards the follower, whereby the pretension with which the locking element acts on the follower is greater than the resetting action of the resetting spring coupled to the follower. The locking element can thereby hold the follower against the action of the resetting spring in a position in which the follower acts on the memory device so that this is unlocked so that during adjustment of the seat from the memory position with the backrest located in the useful position the memory position is adjusted anew. 
   On the other hand, the locking element must be coupled to the backrest so that when folding the backrest forwards the locking element is lifted from the follower. A traction member such as in particular the core of a Bowden cable can be used to couple the locking element to the backrest. 
   The locking element is preferably pivotally mounted and provided on a lever which has at the same time an actuating section for releasing the fixing device of the seat longitudinal guide. 
   The follower in turn is preferably mounted longitudinally displaceable and designed so that it can positively act on the memory device in order to actuate, during adjustment of the seat longitudinal position (with the backrest in the useful position, i.e. with the memory device released), a new setting of the memory position at the same time. 
   If the seat is located outside of its memory position, then the follower is spaced in the seat longitudinal direction from the memory device so that the locking device of the memory device can readily occupy its locked state. For this the locking device is preferably pretensioned in the direction of the locked state. 
   On approaching the memory position with the backrest in the useful position the follower preferably acts on the memory device so that its locking device is released. It is thereby ensured that the memory position during adjustment of the seat with the backrest raised up (i.e. in particular whilst a vehicle occupant is located on the corresponding seat) can be readily set again. 
   Conversely, the follower when the backrest is tilted forwards under the action of its resetting spring, is located in a position in which it does not act on the memory device so that on approaching the memory position with the backrest tilted forwards (i.e. when implementing the easy-entry function), the seat is stopped in the memory position so that the seat position existing before executing the easy-entry function is automatically found once more. 
   In order to facilitate approaching the memory position and releasing the memory device when the backrest is in the useful position, the memory device preferably has a ramp with which the follower on approaching the memory position enters into active connection, i.e. by the follower sliding on the ramp into the memory position. 
   Thus, a hold down member mounted movable (preferably on the seat frame) is provided, which in the memory position of the seat and with the backrest located in the useful position (raised up), acts on the memory device so that its locking device is released, and a ramp is provided (movable together with the locking device in the seat longitudinal direction) with which the hold down member on approaching the memory position with the backrest in the useful position enters into active connection whereby it moves along and on same. 
   The hold down member, when acting on the memory device, releases the locking device and can then furthermore serve as follower, which enables a new setting of the memory position on displacing the seat (with the backrest raised up), thus particularly in a case where the seat is moved together with the vehicle occupant seated thereon to adjust the seat longitudinal position. 
   The ramp provided according to the invention enables, on approaching the memory position with the backrest raised up in the useful position, an automatic release, and if required, entrainment of the locking device of the memory device in that the hold down member is moved by means of the ramp deliberately into a position in which it acts on the locking device so that this is released. As a result when displacing the seat with the backrest raised up an automatic new setting of the memory position can take place. 
   In particular, the solution according to the invention makes it possible to use a longitudinally displaceable but non-pivotal hold down member (mounted rigid transversely to its direction of displacement) for releasing the locking device. Preferably the follower is mounted movable along a straight line, namely the vertical vehicle axis (thus in particular perpendicular to the seat longitudinal direction). The hold down member can be guided by means of the ramp on approaching the memory position so that pivoting is not required. 
   The hold down member can on approaching the memory position slide on the ramp or be moved by rollers or wheels on the ramp. 
   According to one embodiment of the invention, the movably mounted hold down member is mounted spring elastic in its direction of movement so that it can travel over the ramp (inclined in the seat longitudinal direction). Alternatively, the hold down member is movable on elastic wheels or rollers along the ramp. 
   The locking device of the memory device has a locking unit, which is displaceable in the seat longitudinal direction and which defines at the same time the memory position, whereby the locking unit has an associated detent device which has detent points arranged in succession in the longitudinal direction of the seat where the locking unit can be locked relative to the detent device. The locking unit itself comprises a pivotally mounted locking pawl which has a catch element which can engage in the detent device at the different detent points. The hold down member acts on the locking pawl to release this locking device. 
   The ramp is in this case preferably formed on the pivotally mounted locking pawl of the locking unit so that on travelling over the ramp the locking pawl is pivoted increasingly by the hold down member and the locking device is released. The ramp thereby makes it possible in particular for the follower to move up onto the locking pawl on approaching the memory position. 
   The ramp thereby extends across the seat longitudinal direction only over a part of the width of the locking pawl so that the adjoining regions can act as a stop. 
   In a further development of the invention, a stop is provided on the locking device, more particularly on the locking pawl and on approaching the memory position interacts with a stop on the seat frame side (connected to the seat longitudinal guide) so that release of the locking device is blocked until the seat frame has reached the memory position. 
   The hold down member preferably serves at the same time as a follower which, in the memory position of the seat and with the backrest in the useful position, acts on the memory device so that the memory position when adjusting the seat longitudinal position is adjusted together with the seat frame. No separate additional follower is then required for adjusting the memory position when displacing the seat. 
   The hold down member can then, when the backrest is raised up, be held in the position by means of a locking element in which it releases the locking device and can furthermore be coupled to a resetting device, more particularly a resetting spring which, when the backrest is folded forwards, lifts the follower from the memory device. 
   With a locking device having a locking unit, which can be displaced in the seat longitudinal direction and which in the locked state defines the memory position and which is associated with a detent catch device which comprises detent points arranged in succession in the seat longitudinal direction on which the locking unit can lock relative to the detent device, and with a locking pawl pivotally mounted on the locking unit and provided with a detent element which can engage in the detent device at the said detent points, the follower preferably acts on the memory device through the locking pawl. 
   A stop can be provided on the locking pawl on which the follower acts when the backrest is located in its useful position so that the locking unit when adjusting the seat longitudinal position can be entrained with the backrest raised up. The stop can also be formed by an indent in the locking pawl in which the follower engages which is displaceable together with the seat frame in the seat longitudinal direction. 
   Fixing the memory position by means of the locking device is generally not carried out steplessly, i.e. infinitely, but a number of detent points are provided at each of which the memory device can be locked and thus the memory position fixed. This can lead to problems if the seat longitudinal adjustment enables at the same time an infinite adjustment of the seat longitudinal position. For it regularly happens that a seat user moves the seat into a seat longitudinal position and would like to lock it there where a locking of the (non-stepless) memory device is not possible. In such a case it must be ensured that after triggering the easy-entry function (by folding the backrest forwards towards the seat surface) from a position in which the memory device is not locked because the actually set seat longitudinal position was not associated with any suitable detent point of the locking device, this locking can be repeated. For this according to the invention, the memory device has a stop which in the non-locked state of the memory device interacts with an associated stop of the seat frame (which can be provided for example on the seat-side rail of the longitudinal guide) so that the parts of the memory device movable in the seat longitudinal direction are first entrained on sliding the seat forward with the backrest tilted forwards until the locking device of the memory device catches on the next detent point and is thereby locked. With this locking or engagement of the locking device the corresponding stop is moved so that it is no longer in engagement with the associated stop on the side frame side. The seat frame can then be moved further in the seat longitudinal direction whereby the memory device remains in the previously locked memory position. 
   The solution according to the invention enables a very compact arrangement of all the structural groups which ensure the easy-entry function, including the memory device and the fixing device for the seat longitudinal adjustment. In particular the memory device can hereby be arranged completely within the space enclosed by the rails of the longitudinal guide. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Further features and advantages of the invention will now be explained with reference to the embodiment illustrated in the drawings: 
       FIG. 1   a  is a perspective view of parts of a seat frame with a seat longitudinal guide, with a fixing device of the seat longitudinal guide as well as with a programmable memory device for automatically locating a predetermined seat longitudinal position, in a state in which the back rest of the corresponding seat is located in its useful position; 
       FIG. 1   b  is a view according to  FIG. 1   a , in which the rails of the seat longitudinal guide are not shown; 
       FIG. 2  is a view according to  FIG. 1   b  in which the backrest of the seat has been folded further forwards from its useful position; 
       FIG. 3  is a further view according to  FIG. 1   b  in which the backrest of the seat has been folded right onto the associated seat surface; 
       FIG. 4  is a modification of the memory device of  FIGS. 1   a  to  3 ; 
       FIGS. 5   a  to  5   c  are views of the memory device of  FIG. 4  in different phases when approaching the memory position of a seat, whose backrest is located in its useful position; 
       FIG. 6  is a perspective view of a seat frame known from the prior art in a state in which the seat is locked with its backrest raised up in its memory position; 
       FIG. 6   a  is a rear view of  FIG. 6 ; 
       FIG. 7  is a view according to  FIG. 6  in a state in which the backrest is folded forwards in order that the seat can be moved with the backrest folded forwards; 
       FIG. 8  is a view according to  FIG. 6  in a state in which with the backrest raised up in the memory position an actuating lever was actuated to re-set the memory position; 
       FIG. 9  is a view according to  FIG. 6  in a state in which the memory position of the seat is approached with the backrest raised up; 
       FIG. 10  is a view according to  FIG. 6  in a state in which the memory position of the seat is reached with the backrest raised up; 
       FIG. 11  is a diagrammatic view of a seat frame. 
   

   DETAILED DESCRIPTION 
   The seat frame G (seat lower frame) illustrated in side view in  FIG. 11  comprises a seat rail  2  which is mounted movable in the seat longitudinal direction L on a lower rail  1  which is to be fixed on the vehicle body, and a seat side part  8  which is attached height adjustably on the seat rail  2  through front and rear articulated levers. The seat lower frame G has a corresponding arrangement on its other longitudinal side which cannot be seen in  FIG. 11 . 
   Extending between the two seat side parts of the seat frame G is a seat surface which holds a seat cushion on which the vehicle occupant can sit. 
   Furthermore the side parts  8  of the seat frame G each have a bearing point  80  for pivotally mounting a backrest R which is shown in dotted lines in  FIG. 11 . 
   Here, parts of the seat frame are to mean all those component parts which are movable in the longitudinal direction of the seat on the lower rail  1  which is fixed on the body, thus in particular the seat rail  2 , the seat side part  8  and the further component parts of the seat connected thereto. 
   If a vehicle seat of this kind which is displaceable in the longitudinal direction L is used for a two-door vehicle then it is known in order to make entry easier into the back of the vehicle to couple the backrest to the seat longitudinal adjuster, namely so that when tilting the backrest R forwards towards the seat surface which extends between the seat side parts  8  a fixing device associated with the seat longitudinal guide  1 ,  2  is released and the seat can be moved forwards with the backrest tilted forwards. This is the so-called easy-entry function. 
   In the following, there is first an explanation, using a seat assembly known from WO 00/55002 (see corresponding U.S. Pat. No. 6,631,952 and illustrated in  FIGS. 6 to 10 , of the basic principle of the easy-entry function when using a programmable memory device for automatically locating a predeterminable seat longitudinal position. For further details on this reference is made to WO 00/55002 (see corresponding U.S. Pat. No. 6,631,952) which in this respect is an explicit part of the present specification. 
   In the perspective front view according to  FIG. 6  and the associated rear view according to  FIG. 6   a  can be seen a rail  101  fixed on the body and a seat rail  102  movable thereon in the seat longitudinal direction L whereby the rail  101  fixed on the body is provided with a fixed ratchet rail  107  having several ratchet openings  170  arranged in succession in the seat longitudinal direction L. The seat rail  102  supports the remaining components of the seat frame, see  FIG. 11 . 
   The seat rail  102  is lockable relative to the rail  101  fixed on the body by means of a fixing device  120 . This can be a conventional fixing device for a seat longitudinal adjuster. In  FIGS. 6 and 6   a  the housing, a pivotally mounted actuating element  120   b  and a torsion spring (shown in  FIG. 7 ) of a known fixing device  120  acting on the actuating element  120   b  are shown, with the housing fixed on the seat rail  102 . A torsion spring (not shown) serves inter alia to remove play from the assembly to prevent rattling noises. 
   This fixing device  120  comprises by way of example according to DE 299 10 720 U1 a number of locking teeth arranged inside the housing and pretensioned—by means of springs mounted in the form of coil springs in the housing—elastically towards a detent device fixed on the rail  101  on the side of the body, but not shown in  FIGS. 6 and 6   a . As a result of the pretension acting on the locking teeth the locking teeth which are associated with the seat rail  102  automatically engage in the detent device fixed on the body so that the seat longitudinal adjustment is locked unless the locking teeth are disengaged from the detent device by means of the actuating element  120   b  provided for this purpose (see  FIG. 7 ). 
   Since the actuating element  120   b  ( FIG. 7 ) of the fixing device  120  is pretensioned by means of the spring assembly  120   a  which consists of the springs mounted inside the housing and acting on the locking teeth, and the torsion spring mounted outside of the housing (not shown), against the direction in which it has to be swivelled for releasing the fixing device  120 , the fixing device  120  can only then be released if a force is exerted on the actuating element  120   b  against the action of the spring assembly  120   a.    
   In order to release the fixing device  120  the actuating element  120   b  can be directly actuated on one side by a seat user seizing an actuating lever  109  pivotally attached to the seat frame and having a cross bar by means of the actuating handle  190  provided for this (not shown in  FIG. 6   a ) and swiveling this counter-clockwise whereby the actuating element  120   b  moves down against the pretension of the spring assembly  120   a . On the other hand, the fixing device  120  can also be released by folding the seat back forwards whereby the seat back is coupled to the actuating lever  109  through a Bowden cable which has a cable  121   b  and whose Bowden tube (not shown) is supported on a Bowden cable support  121 . Furthermore, a gearing part  122  is mounted on the swivel axis of the actuating lever  109  by means of an axle shaft  124 , the gearing part having a guide  122   a  as well as a mounting  122   b  for the cable  121   b  of the Bowden cable. This gearing part  122  converts a tightening of the cable  121   b  when folding the backrest forwards into a swivel movement which in turn is transferred through two arms  123  of the gearing which engage round the actuating lever  109  to same. The actuating lever  109  thereby swivels clockwise when folding the backrest forwards and releases the fixing device  120  through the actuating element  120   b.    
   Furthermore a cable nipple  168  is fixed, e.g. squashed, on the cable  121   b  of the Bowden cable between the Bowden cable support  121  which is fixed by means of a fixing plate  121   a  on the seat rail, and the gearing  122 . The cable nipple  168  is associated with a switch element in the form of a switch lever  106  which is mounted by means of a bearing bushing  165 , a stepped bolt  165   a  as well as a screw  166  to pivot about an axis formed by the longitudinal axis of the stepped bolt  165   a , and which is at the same time fixed on the seat frame (not shown) or its seat rail  102 . The switch lever  106  has in an upper section  161  a stop  162  which is mounted directly adjacent the cable nipple  168  and on which the cable nipple  168  can act in the seat longitudinal direction whereby the switch lever  106  is pivoted. 
   The second end section of the switch lever  106  mounted underneath the bearing bush  165  and stepped bolt  165   a  forms an actuating section  160  associated with an actuating section of a locking pawl  104  of the memory device. The actuating section of the locking pawl  104  is thereby formed by an actuating face  140  on the top side of the locking pawl. 
   The switch lever  106  is here locked in the position illustrated in  FIGS. 6 and 6   a  in which the actuating section  160  acts on the actuating surface  140  of the locking pawl  104 , through a projection  191  of the actuating lever  109  on which the upper section  161  of the switch lever  106  is vertically (across the seat longitudinal direction L) supported by a stop  163 . The torque required for this is applied by the spring assembly  120   a  of the fixing device  120  which acts on the lever projection  191  through the actuating element  120   b  and the actuating lever  109 . 
   As an alternative or in addition the perpendicular position of the switch lever  106  can also be supported by a spring mounted directly on the switch lever  106  (not shown) or in that the switch lever  106  is mounted with sufficient friction which cannot be overcome by the action of the compression spring  400  of the locking pawl  104 . 
   The locking pawl  104  itself is as can be seen from  FIG. 6   a  pivotally mounted on a bearing pivot  155  of a slide  105  which is guided with a base body  150  in the seat longitudinal direction L movable next to the detent openings  170  of the ratchet rail  107 . The slide has in its base body  150  a recess  152  in which the compression spring  400  is mounted which acts underneath the actuating surface  140  of the locking pawl  104  on the latter and thereby pretensions the locking pawl  104  so that a detent hook  141  arranged at the other end of the locking pawl  104  has the tendency to engage in the ratchet rail  107 . In the situation illustrated in  FIGS. 6 and 6   a  in which the seat is locked in the memory position with the backrest not folded forwards, the locking pawl is blocked so that the actuating section  160  of the switch lever  106  is supported on the actuating face  140  of the locking pawl  104  so that the latter cannot swivel about the bearing pin  155  in order to bring the detent hook  141  into engagement with the ratchet rail  107 . 
   In the situation illustrated in  FIGS. 6 and 6   a , a counter stop  144  of the locking pawl  104  is in contact with a stop  132  of a stop element  103  which is fixed by fixing screws  136  on the seat rail  102 . Furthermore, a follower  143  of the locking pawl  104  which adjoins the counter stop  144  at the top is located in engagement with an engagement region  134  of the stop element  103 . 
   If, in the state of the seat illustrated in  FIGS. 6 and 6   a  in which the seat is locked in the memory position, the backrest is folded forwards then the cable  121   b  of the Bowden cable is tensioned and moved towards the rear seat end (on the backrest side). 
   According to  FIG. 7 , on the one hand, the actuating lever  109  is pivoted through the gearing part  122  and the arms  123  counter-clockwise whereby it acts on the actuating element  120   b  and releases the fixing device  120 . On the other hand, the cable nipple  168  which is squashed with the cable  121   b  is moved towards the rear seat end and thereby acts on the stop  162  in the upper section  161  of the switch lever  106 . The switch lever  106  is thereby swivelled counter-clockwise whereby its actuating section  160  is lifted from the associated actuating face  140  of the locking pawl  104 . This swivel movement of the switch lever  106  is possible since this is no longer blocked through the lever projection  191  which was indeed pivoted downwards together with the actuating lever  109 . With the switch lever  106  having released the locking pawl  104  the latter now swivels as a result of the action of the compression spring  400  (see  FIG. 6   a ) about the bearing pivot  155  of the slide  105  until the detent hook  141  engages in an opening  170  of the ratchet rail  107 . The locking pawl  104  and thus the memory device overall is thereby locked. 
   The swivel movement of the locking pawl  104  has moreover the result that the follower  143  of the locking pawl  104  and the engagement area  134  of the stop element  103  move out of engagement. This is necessary in order that the seat frame can be moved since otherwise movement of the seat would be blocked by the locked memory device. 
   The cable nipple  168  thereby serves here as locking means which with the backrest folded forwards acts on the switch lever  106  so that the locking pawl  104  cannot be released by means of the switch lever  106 . 
   The arrangement is designed so that when tilting the backrest forwards the detent hook  141  can engage under the action of the compression spring  400  already in a detent opening  170  before the fixing device  120  is released so far that the seat rail  102  can be displaced relative to the rail  101  fixed on the body. A reliable storage of the actual seat longitudinal position as the memory position is hereby guaranteed. If the detent hook  141  cannot engage directly in a detent opening  170  because the seat is positioned such that the detent hook  141  under the action of the compression spring  400  strikes on a web between the two detent openings  170 , then the detent hook  141  only engages in the next detent opening  170  which it passes after a slight displacement of the seat frame in the seat longitudinal direction L. In such a case a slight deviation arises between the seat longitudinal position when folding the backrest forwards and the then subsequently stored memory position. 
   In the state illustrated in  FIG. 7 , which was reached by folding the backrest forwards, the seat frame can now be pushed forwards with the backrest folded forwards in the seat longitudinal direction L in order to make it easier for a passenger to enter or place objects in the back of the vehicle. 
   If the seat is then moved back with the backrest folded forwards it is automatically stopped at the latest in the memory position defined by the locking pawl  104 . For on reaching the memory position the stop  132  of the seat frame moves into contact with the counter stop  144  of the memory device whereby a further movement of the seat frame backwards is prevented. 
   If then the backrest is folded back again into its function position then the tension of the cable  121   b  is released and the switch lever  106  as well as the actuating lever  109  with the projection  191  fixed thereon move back into the position illustrated in  FIGS. 6 and 6   a . If then the actuating lever  109  is swiveled counter-clockwise in order to release the fixing device  120  then the position illustrated in  FIG. 8  is adopted. 
   On manually pivoting the actuating lever  109  by means of the actuating handle  190  provided for this purpose the fixing device  120  is indeed released through the actuating element  120   b  so that the seat frame can be moved in the seat longitudinal direction L on the rail  101  fixed on the body; however here—as opposed to folding the backrest forwards—the switch lever  106  remains in its upright position in which its actuating section  160  acts vertically on the actuating surface  140 . It is hereby prevented that the locking pawl  104  is locked through the action of the compression spring  400 . 
   As a result of the lever projection  191 , which is swiveled down according to  FIG. 8  and which consequently does not adjoin the associated stop  163  of the switch lever  106 , the vertical position of the switch lever  106  must be secured for example by a suitable formation of the actuating surface  140  of the locking pawl  104 . The actuating surface  140  can hereby be curved so that under the action of the compression spring  400  of the locking pawl  104  it exerts no torque on the actuating section  160  of the switch lever  106  which would cause a pivotal movement of the switch lever  106  counter-clockwise. 
   In other words, the interaction of the actuating face  140  of the locking pawl  104  with the actuating section  160  of the switch lever  106  must be such that through the forces introduced by the compression spring  400  from the locking pawl  104  no pivotal movement of the switch lever  106  counter-clockwise is initiated. A pivotal movement of the switch lever  106  in the clockwise direction is, however, blocked by the cable nipple  168 . 
   Alternatively the perpendicular position of the switch lever  106 —as already mentioned—can also be secured by means of a suitable spring element (not shown) or by sufficiently large friction forces. 
   In short, the actuation of the actuating lever  109  in the memory position of the seat (with the backrest not folded forwards) leads to, on the one hand, the fixing device  120  being released while at the same time the locking pawl  104  and thus the memory device remain overall in the released state, which already existed before pivoting the actuating lever  109 , see  FIGS. 6 and 6   a . Moreover, the follower  143  of the memory device engages in the engagement region  134  of the stop element  103  on the seat rail side. 
   In this state, movement of the seat frame in the seat longitudinal direction L leads to, at the same time, the locking pawl  140  being entrained so that during sliding of the seat, a new memory position is set also at the same time. The newly set memory position which corresponds to the seat longitudinal position newly set by sliding the seat frame is, however, not already locked when the actuating lever  109  is finally let go. For this has, according to  FIGS. 6 and 6   a , at first only the result that the fixing device  120  is locked and thus the seat rail  102  is locked relative to the rail  101  fixed on the body. Locking of the memory device, however, only happens according to  FIG. 7  when in the new seat longitudinal position the seat back is folded forwards. Thus, in the present embodiment, the memory device is then only locked when the seat is moved forwards with the backrest folded forwards within the scope of the easy-entry function. 
     FIG. 9  shows the seat frame after it was first pushed forwards with the seat back folded forwards in the seat longitudinal direction L whereby the locking pawl  104  has been left back locked in the original seat position, and after then the backrest was folded back again into its function position. Furthermore the actuating lever  109  is pivoted so that the fixing device  120  is released and the seat frame can be adjusted in the seat longitudinal direction selectively forwards or backwards. In each seat longitudinal position which is hereby reached the seat frame can be locked by the fixing device  120  relative to the rail  101  fixed on the body by letting go the actuating lever  109 . 
     FIG. 10  finally shows the position of the seat frame when the latter is moved back with the backrest upright into the memory position. The switch lever  106  thereby stops with its actuating section  160  against a projection  140   a  which projected vertically upwards from the actuating surface  140  of the locking pawl  104 . This is due to the fact that the locking pawl  104  is located in the locked state in which it engages by its detent hook  141  (see  FIG. 6   a ) in a detent opening  170  of the ratchet rail  107 . Through the inclined position of the actuating face  140  of the locking pawl  104  associated with this the pawl exerts on the actuating section  160  of the switch lever  106  a torque with a component both parallel and perpendicular to the seat longitudinal direction L. As a result of this the switch lever  106  is pivoted counter—clockwise and its actuating section  160  engages with the projection  140   a  of the locking pawl  104 . This has the effect that the locking pawl  104  remains locked when the seat lower frame has reached the memory position shown in  FIG. 10 . 
   In short, the actuating face  140  in the locked state of the locking pawl  104  interacts with the actuating section  160  of the switch lever  106  so that the latter is pivoted when the seat is pushed with the backrest upright into the memory position whereby release of the locking pawl  104  is prevented. 
   (If the seat is pushed back with the backrest folded forwards into the memory position then the switch lever  106  as a result of the action of the cable nipple  168  is swiveled anyhow, see  FIG. 7  so that also in this case no release of the memory device can take place). On the other hand, the actuating face  140  of the locking pawl  104  and the actuating section  160  of the switch lever  106  interact in the released state of the locking pawl  104 , see  FIG. 6 , so that the locking pawl  104  remains released, as described in further detail above with reference to  FIG. 6 . 
   As a result of the locked state of the locking pawl  104 , the seat frame on reaching the memory position is automatically stopped when the stop  132  of the stop element  103  on the seat frame side becomes blocked with the counter stop  144  of the memory device (see  FIG. 6   a ). 
   If then in the memory position the actuating lever  109  is let go the latter is swiveled clockwise through the action of the spring assembly  120   a  of the fixing device  120  until the fixing device  120  is again locked. At the same time, through the projection  191  of the actuating lever  109  which acts on the angled stop  162  in the upper section  161  of the switch lever  106 , the switch lever  106  is pivoted clockwise into its perpendicular position whereby the switch lever  106  acts by its actuating section  160  on the actuating face  140  of the locking pawl  104  and releases same (against the action of the compression spring  400 )—(which requires a suitable design of the spring assembly  120   a ). 
   The seat is then located again in the state explained with reference to  FIGS. 6 and 6   a  with the backrest raised up in the memory position. 
   A further development according to the invention of the known vehicle seat described above with reference to  FIGS. 6 to 11  will now be explained with reference to  FIGS. 1   a  to  3 . The vehicle seat and its seat frame illustrated in  FIGS. 6 to 11  substantially agree regarding the design of the rail longitudinal guide  101 , the seat rail  102 , the design of the fixing device  120  as well as regarding the design of the memory device  104 ,  105 ,  107 , with the vehicle seat described with reference to  FIGS. 6 to 11 . These features will therefore not be described in finer detail. Instead, in this respect reference is made to the explanations provided above on  FIGS. 6 to 11  whereby using matching reference numerals for corresponding component parts in  FIGS. 1   a  to  3 , on the one hand, and in  FIGS. 6 to 11 , on the other hand, the required connections are provided. 
   The essential characteristic features of the embodiment illustrated in  FIGS. 1   a  to  3  of the invention lie in the formation of a follower and an associated locking element which enable an automatic re-adjustment of the memory position when the vehicle seat is moved with the backrest raised up (backrest in useful position) and which prevent a resetting of the memory position if the vehicle seat is displaced for executing an easy-entry function with the backrest folded forwards on the seat surface. These two function groups will now be described with reference to  FIGS. 1   a  to  3 . 
   In  FIG. 1   a  a perspective view shows a seat longitudinal guide  101 ,  102  consisting of a lower rail  101  to be mounted fixed on the body and an upper rail  102  which supports the seat frame. This longitudinal guide  101 ,  102  enables an adjustment of the seat longitudinal position (position of the seat frame in the seat longitudinal direction L). 
   In order to lock a previously set seat longitudinal position a fixing device  120  provided with elastically pretensioned locking teeth Z is mounted on the top rail  102  on the seat side (seat rail) and whose locking teeth Z can engage in associated detent openings of the lower rail fixed on the body in order to lock the two rails  101 ,  102 . Through the elastic pretension of the locking teeth Z in the direction of the associated detent openings the fixing device  120  has the tendency to lock the two rails  101 ,  102  together if this is not released by action on an actuating element  102   b  provided for this purpose (see  FIGS. 7 to 10 ). This action can—as already mentioned with reference to FIGS.  6  to  11 —take place on one side by a direct release of the fixing device through a suitable actuating lever or indirectly by folding the backrest forwards to trigger the easy-entry function. 
   Furthermore from  FIG. 1   a , and in particular  FIG. 1   b  in which the rails  101 ,  102  are not shown, the essential constituent parts of a memory device  104 ,  105 ,  107  can be seen, namely a slide  105 , a locking pawl  104  swivel mounted on the slide  105 , as well as a ratchet rail  107  provided with detent openings  170 , in which a detent hook  141  of the locking pawl  104  can engage for locking a previously set memory position. Also here reference is made to the explanations on  FIGS. 6 to 11 . 
     FIGS. 1   a  and  1   b  show a section of the seat frame formed according to the invention in a state in which the seat with the backrest raised up (in its useful position) is locked in a memory position by means of the fixing device  120 . 
   In this state a hold down member in the form of a follower  203  acts on the locking pawl  104  of the memory device so that the locking pawl  104  is lifted by its detent hook  141  out from the ratchet rail  107 . The follower  203  is mounted longitudinally displaceable on the seat rail  102  or on a holding part  201  fixed on the seat rail  102  and comprises an elongated base body  230  on whose lower end facing the locking pawl  104  is fixed or formed a follower element  234  which is provided with an entrainment opening  235 . This follower  203  is pretensioned by means of an elastic element  232  in the form of a compression spring (resetting spring), which is supported on one side on the holding part  201  and on the other on a projection  231  protruding from the base body  230  of the follower  203 , in a direction away from the locking pawl  104  so that it has the tendency to lift away from the locking pawl  104 . This is, however, prevented by a locking element  221  on the base body  220  of a lever  202 , which is pivotally mounted above an axis  225  and which is pretensioned by means of a spring element  228  in the form of a torsion spring in the direction of the projection  231  of the follower  203  so that the locking element  221  presses the follower against the action of the elastic element  232  provided on the follower against the locking pawl so that the detent hook  141  of the locking pawl  104  is lifted out from the ratchet rail  107 . At the same time a projection  145  of the locking pawl formed as a detent nose engages in the entrainment opening  235  of the follower  203 . 
   This is achieved in that the locking element  221  which is pretensioned by the torsion spring  228  exerts on the follower  203  a force in the direction of the locking pawl  204  which is greater than the force acting as a result of the compression spring  232  in the opposite direction. The detent hook  141  is thus lifted out from the detent openings  170  of the ratchet rail  107  and the locking pawl  104  can during displacement of the seat with the backrest raised up be entrained in the seat longitudinal direction L so that the memory position is set anew at the same time as the seat is displaced. 
   If in the state of the seat illustrated in  FIGS. 1   a  and  1   b  the backrest is folded forwards towards the seat surface, the cable  121   a  of a Bowden cable  121   a ,  121   b  is thereby tensioned which is connected by one end to the seat back and by the other end to the base body  220  of the pivotally mounted lever  202 . The lever  202  is hereby pivoted so that the locking element  221  is lifted from the projection  231  of the follower  203  and thus the follower is lifted from the locking pawl  104  under the action of the compression spring  232 . Since the locking pawl  104 —as explained with reference to FIGS.  6  to  10 —is again set under pretension by means of a spring element so that the detent hook  141  of the locking pawl  104  has the tendency to engage in one of the detent openings  170  of the ratchet rail  107  then the locking pawl  104  is locked in its actual position. This corresponds to a locking of the memory device  104 ,  105 ,  107  overall. This state is shown in  FIG. 2 . 
   The mechanism is designed so that the locking of the memory device  104 ,  105 ,  107  is carried out during folding the backrest forwards about 20° to 40° from a vertical useful position. The locking of the memory device thus takes place already in the first stage (phase) of activating the easy entry mechanism by folding the backrest forwards towards the seat surface. The fixing device  120  is locked in this first phase of folding the backrest forwards as before so that no displacement of the seat can take place in the longitudinal direction L. 
   This is only possible on folding the backrest further forwards whereby according to  FIG. 3  an actuating section  222  provided on the pivotally mounted lever  202  acts on the actuating lever  109  of the fixing device  120  illustrated in  FIGS. 7 to 10  so that the fixing device  120  is released. This then enables a displacement of the seat in the longitudinal direction L. 
   According to this, displacement of the seat in the longitudinal direction L is only possible on folding the backrest forwards to execute the easy-entry function after the locking pawl  104  of the memory device  104 ,  105 ,  107  has been locked. Thus, the memory position which exists when folding the backrest forwards is reliably fixed before a displacement of the seat can take place with the backrest folded forwards. This memory position can then be located when subsequently moving the seat back again, as explained above with reference to  FIGS. 6 to 10 . It is thus prevented that when implementing the easy-entry function displacement of the seat with the backrest folded forwards can take place before the starting position of the seat is fixed as memory position. 
   The entire assembly is thereby very compact as a result of the ability of the follower  203  to slide substantially perpendicular to the extension direction L of the seat longitudinal guide as well as through the pivotal bearing of the lever  202  with the locking element  221  and is located substantially within the space enclosed by the rails  101 ,  102  of the rail longitudinal guide or only projects upwards from same. 
   If according to  FIGS. 1   a  to  3  the backrest of the seat is folded forwards in order to trigger the easy-entry function then the problem may arise that the detent hook  141  of the locking pawl  104  cannot engage in one of the detent openings  170  of the ratchet rail  107 . For the fixing device  120  enables as a rule an infinite adjustment of the seat longitudinal position, see the fixing device described in DE 299 10 720 U1, while here for locking the memory position a finely stepped (thus no infinite) engagement is provided (by using the ratchet rail  107  with detent openings  170 ). Thus it may happen that when folding the backrest forwards the detent hook  141  of the locking pawl  104  cannot engage in a detent opening  170  but stands up on the edge. Initially no locking of the memory position is then possible. 
   If now with the backrest folded forwards the seat frame and thus also the seat rail  102  are moved forwards out from the memory position in the seat longitudinal direction (easy-entry function) then the locking pawl  104  is thereby entrained together with the slide  105  along a little since a stop  127  provided on the seat rail  102  acts on an associated stop  147  on the locking pawl side. The locking pawl  104  and slide  105  are thereby entrained only so far until the detent hook  141  of the locking pawl  104  can engage completely in the next detent opening  170  of the ratchet rail  107  under the action of the spring element provided on the locking pawl. The locking pawl  104  and thus the locking device  104 ,  107  of the memory device  104 ,  105 ,  107  as a whole are then locked in that memory position which lies closest to the seat longitudinal position in which the fixing device  120  was locked prior to folding the backrest forwards. 
   In the locking state in which the detent hook  141  of the locking pawl  104  engages in a detent opening  170  of the ratchet rail  107 , the stop  147  on the locking pawl side is located beneath the stop  127  on the seat rail side so that these stops  127 ,  147  can no longer move into active connection with each other. The seat can then be moved forwards further in the seat longitudinal direction L whereby the locking pawl  104  and slide  105  remain in the previously locked memory position. 
     FIG. 4  shows a modification of the embodiment of  FIGS. 1   a  to  3 , namely with a view of approaching the memory position when sliding back the seat with the backrest raised and thus located in the useful position. This relates in particular to the case where the seat is moved backwards towards the memory position whilst a vehicle occupant is seated on the seat. 
   If the seat is pushed with the backrest raised up into the memory position after it previously has been pushed out from the memory position with the backrest folded forwards, thus without entrainment of the locking pawl  104  and slide  105  then the follower  203  on reaching the memory position strikes the locking pawl  104 . The follower  203  is thereby pressed down by means of the locking element  221  (not shown in  FIG. 4 ) towards the locking pawl  104  of the memory device owing to the backrest located in the useful position. 
   In the state illustrated in  FIG. 4 , in order to enable reaching the actual memory position in which the follower  203  engages positively in the locking pawl  104 , the locking pawl  104  has a ramp  146  on which the lower end section  234 ′ of the follower  203  can slide up to an indent  145 ′ of the locking pawl  104 . This is shown in  FIGS. 5   a  to  5   c  whereby the follower  203  then engages in the memory position with its lower end section  234 ′ into the associated indent  145 ′ of the locking pawl  104 . The lower end section  234 ′ of the follower  203  as well as the indent  145 ′ of the locking pawl  104  then act as stops which enable entrainment of the locking pawl  104  together with the slide  105  during further displacement of the seat. 
   The ramp  146  thereby extends only over a part of the width of the locking pawl  104  (extension perpendicular to the seat longitudinal direction L and to the movement direction of the follower  203 ) so that adjoining areas  148  of the locking pawl  104  can act as stops in order to define the memory position in the locked state of the locking pawl  104 . 
   Since the follower  203  on approaching the memory position with the backrest raised up and located in the useful position is pressed down towards the locking pawl  104 , on approaching the memory position it also lifts at the same time the detent hook  141  of the locking pawl  104  out from the associated ratchet rail  107 . Only then is the common further displacement possible of the seat on one side and of the locking pawl  104  and slide  105  on the other. 
   Through the interaction of the stop  127  on the seat frame side with the stop  147  on the locking pawl side when approaching the memory position, whereby the stop  147  of the locking device (locking pawl  104 ) on the locking pawl side is supported vertically (parallel to the direction of movement of the follower  203 ) on the stop  127  on the seat frame side, while the follower  203  slides along the ramp  146 , lifting of the locking pawl  104  out from the associated ratchet rail  107  is only possible after the stop  147  on the locking pawl side has passed the stop  127  on the seat frame side. The follower  203  then engages in the indent  145 ′. Since the stops  127 ,  147  first prevent a pivotal movement of the locking pawl  104  and the ramp  147  runs inclined in the seat longitudinal direction, the follower  203  is first raised on travelling over the ramp  146 . The follower  203  which is mounted resiliently (by means of the spring  232 ) hereby carries out a compensating movement in the vertical direction. 
   In short, the embodiment of the invention illustrated in  FIGS. 4 to 5   c  enables, when approaching the memory position with the backrest raised up in the useful position, an automatic entrainment of the parts  104 ,  105  of the memory device located in the memory position so that when adjusting the seat with the backrest raised up an automatic re-setting of the memory position can take place. If, however, the memory position is arrived at with the backrest folded forwards onto the seat, then the follower  203  is located under the action of the compression spring  232  in a position in which it cannot act on the locking pawl  104  of the memory device  104 ,  105 ,  107 . The locking pawl  104  thereby remains together with the slide  105  locked in the memory position in which the seat is then automatically stopped so that the previously set memory position has been relocated when sliding the seat back with the backrest folded forwards—as desired. 
   As can be seen in particular from  FIG. 4  the follower  203  is only first able to move onto the locking pawl  104  through the ramp  146  since otherwise the follower  203  on approaching the memory position would stop with the locking pawl  104  and could not move onto same in order to release the locking device. In other words, the hold down member is lifted by means of the ramp (towards the indent  145 ′).