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You are an expert at summarizing long articles. Proceed to summarize the following text: 
BACKGROUND OF THE INVENTION 
     The invention concerns a window lifter with a guide rail affixed on a base part. 
     It is generally known to affix guide rails of a window lifter, in which rails the window pane is driven along its closing and opening movement, on a base part. The base part is usually designed as a door inner panel or an assembly carrier. The guide rails are screwed, riveted, or welded or attached by snap elements to this base part. The guide rails rest on the base part with a flat face. 
     Disadvantageous in such connections is the fact that because of the fixed mounting of the guide rails on the base part, subsequent alignment of the guide rails is not possible, such that stresses may develop inside the window lifter system. 
     From DE 196 11 074 A1, an arrangement for the adjustment of a frameless window pane by a tilting motion at right angles to the longitudinal axis of the motor vehicle is known, wherein separate adjustment and locking means are provided for each guide rail. One of the guide rails is equipped with a slotted guide and the other guide rail has an adjustment screw, which is equipped with a self-locking thread. The guide rail with the slotted guide is first affixed loosely on the base part. By rotation of the adjustment screw, the guide rail is pivoted at a right angle to the longitudinal axis, and this rotational movement is transferred by the window pane to the guide rail with the slotted guide such that the position of the two guide rails as well as the window pane changes uniformly. 
     Such an arrangement does enable the adjustment of the window pane by a tilting motion; however, the coordination of the guide rail seat with the base part is only imprecisely possible since the two assemblies are placed only loosely on each other. Stresses due, for example, to twisting guide rails because of manufacturing inaccuracies cannot be compensated by this type of attachment or adjustment. Likewise, an adjustment of the guide rails with spherically curved window panes is difficult. 
     SUMMARY OF THE INVENTION 
     The object of the invention is to provide a window lifter with a guide rail affixed on a base part, which is simple and precise to adjust and which prevents stressing of the window lifter system. 
     The design of the seat and a corresponding mating part enables tilting without the guide rail and the base part being able to be displaced relative to each other. On the one hand, this makes possible the adjustability of the guide rail for exact, problem-free operation of the window lifter, since a specific affixing of the window pane has already occurred; on the other, no unwanted tilting or displacement of the rail occurs such that, overall, assembly accuracy is increased and assembly time is reduced. 
     An improvement of the invention provides that the seat and the mating part prevent displacement of the base part and the guide rail relative to each other in at least one direction, for example, by means of a cylindrical design of the seat and of the mating part, whereby the seat and mating part oppose each other in a mirror image. Thus, unwanted tilting around a specific axis can be prevented, whereby the accuracy of the assembly is rendered easier in those cases in which no adjustment around multiple axes must be made. 
     Through connection of the guide rail with the base part by means of a ball-cup mating it is possible to rotate the guide rails of the window lifter in multiple directions such that an exact adjustment of the guide rails can occur and no stresses occur within the window lifter system. Especially in the case of highly curved window panes, adjustability in multiple directions, which is accomplished by means of a ball-cup mating of the guide rails with the base part, is necessary. 
     In one embodiment of the invention, at least one ball- or cup-shaped seat is arranged on the base part or on the guide rail. By means of this seat, the ball-cup mating is realized, and a movable connection between the guide rail and the base part is permitted. For technical production reasons, it is advantageous to design this seat in one piece on the base part, for example, by an appropriate shaping process, such as deep drawing or pressing. It is possible to produce the seat already at the time of production of the base part in a molding operation such as casting or injection molding. 
     In an advantageous embodiment, the seat is designed as a cup-shaped recess in a conical or spherical projection. Thus, a base for the cup-shaped recess is more or less formed, yielding a relatively large radius of motion of the component (base part or guide rail) with the cup-shaped recess relative to the ball-shaped mating part. The conical or spherical projection in which the cup-shaped recess is formed can be formed on either the base part or the guide rail. The projection can likewise be formed in the guide rail or the base part in a shaping or molding operation. 
     As an alternative to the ball shape of the seat, provision is made to design the seat and, accordingly, the mating part as a barrel-shaped or cylindrical shape, whereby the seat has the mirror-image shape of the mating part. The adjustability of the guide rail can be realized with one of the mating pairs either through a combination of a ball-cup mating with a cylinder-mounting or by an adjustment arrangement on an attachment region of the guide rail, for example, by an adjustment bolt with a check nut. 
     Advantageously, a through-hole, through which an affixing means can be passed, is provided in the seat to enable an appropriate connection of the base part with the guide rail. The through-hole is formed either on the guide rail or on the base part and is advantageously provided as an oblong slot, thus yielding an increased adjustment range of the guide rail in the direction of the lengthwise path of the oblong slot. It is also possible to select the cross-section of the through-hole substantially larger than the cross-section of the affixing means such that there is increased movability of the guide rail relative to the base part in all directions. In the selection of the cross-section of the through-hole, consideration must be given to the fact that the guide rail is attached to the base part by the affixing means. 
     By designing the affixing means as a releasable connecting element, for example, as a screw, simple adjustment of the position of the guide rails relative to the base part is possible. Likewise, this makes it possible to perform subsequent adjustment or, in the event of repair or damage to the window lifter system, readjustment of the guide rails. 
     In an advantageous embodiment, the affixing means has a contact zone adjacent the base part and a contact zone adjacent the guide rail, whereby the respective contact zones are designed corresponding to the seat of the base part or of the guide rail. If, for example, the base part is designed flat, the corresponding contact zone is also designed flat. With a ball-shaped design of the base part or of the guide rail, the contact zone is, accordingly, cup-shaped to accommodate the ball-shaped zone of the guide rail or of the base part. The contact zones are shaped such that the guide rails can swivel relative to the base part. 
     In one embodiment of the invention, the affixing means is designed as an affixing screw which is connected only by at least an affixing nut with the base part and the guide rail. It is advantageous in this case if the affixing nut has a ball- or cup-shaped head corresponding to the seat of the base part or of the guide rail. This ensures that the head of the affixing nut comes into full-surface connection with the correspondingly shaped seat. 
     In a variant of the invention, the affixing means is nonreleasably connected with the guide rail, for example, by welding, soldering, or by extrusion. This reduces the number of parts that are necessary to affix or assemble the guide rail to the base part. In an improvement of the invention, the affixing means is designed as a threaded segment on which a curved contact zone is connected. This contact zone serves as a ball- or cup-shaped seat and enables an appropriate displacement of the correspondingly designed mating part. Provision is made, for example, to design the contact zone ball-shaped on the guide rail and to realize a cup-shaped seat of the base part such that the guide rail and the base part can the swivel in multiple planes. 
     Provision is further made that the mating part and the affixing means form one assembly unit such that the mating part does not have to be designed in one part in the guide rail, but instead can be produced and mounted separately, for example, as a special screw. This is especially advantageous if the mating part must have special hardness and thus must be made from a different material. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Exemplary embodiments of the invention are explained in the following with reference to the figures. They depict: 
     FIG. 1 a cross-sectional depiction through a motor vehicle door; 
     FIG. 2 an affixing screw in partial cross-section; 
     FIG. 3 a cross-sectional depiction through a seat; 
     FIG. 4 an affixing nut in partial cross-section; 
     FIG. 5 a cross-sectional depiction through a seat in a ball-shaped projection; 
     FIG. 6 a partial cross-sectional view of an affixing means nonreleasably connected to a guide rail, and 
     FIG. 7 a cross-sectional depiction through a motor vehicle door with a cylindrical or barrel-shaped seat. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 depicts a motor vehicle door  1  with an exterior panel  2  and a base part  20 , whereby the base part is designed as a door inner panel. In the cavity formed by the exterior panel  2  and the door inner panel  20 , a window pane  3  is mounted displaceable along the guide rail  10 . The drive of the window pane  3  to adjust the position is not shown. The guide rail  10  is connected to the door inner panel  20  by a ball-cup mating, whereby a spherical seat  30 , which is connected to the guide rail  10  by means of an affixing means  55 , is designed on the door inner panel  20 . The affixing means  55  is designed as an affixing screw and is affixed both to the guide rail  10  and to the seat  30  of the door inner panel  20 . In this embodiment the affixing means forms a mating part  300  with the seat  30  and they form a functional unit. FIG. 7 depicts and explains a different embodiment of the mating part. 
     One example of such an affixing screw  55  is depicted in FIG. 2, in which an affixing screw  55  with a threaded segment  570 , on which a contact zone  57  is connected, which is designed corresponding to the curve of the seat  30 , is depicted. The threaded segment  570  is inserted through a through-hole  40  of the seat  30 , as depicted cross-sectionally in FIG.  3 . The through-hole  40  may be designed either as an oblong slot to permit an increased radius of movement in one direction, or have a larger cross-section in all directions than the cross-section of the threaded segment  570  such that movability of the affixing screw  55  on the surface of the seat  30  in all directions is enabled. Of course, the cross-section of the through-hole  40  is not larger than the cross-section of the contact zone  57 , so that a connection does in fact occur. 
     As depicted in FIGS. 2 and 3, the curvature of both the seat  30  and contact zone  57  is cap-shaped such that movability in all directions is possible. However, it is also conceivable that the seat  30  have a barrel shape and the contact zone  57  be shaped accordingly. 
     FIG. 4 depicts an affixing nut  56  which has a round head whose curve is designed to correspond with the curve of the seat  30  in FIG.  3 . The installation of the affixing screw  55  occurs in that the threaded segment  570  is introduced from above through the through-hole  40  of the seat  30  according to FIG.  3  and is screwed on with the affixing nut  56  which is introduced into the seat  30  from below. 
     On the side of the affixing screw  55  turned away from the seat  30 , an additional threaded segment  580  is provided, to which a contact zone  58  is adjacent, which comes into contact with a guide rail (not shown). The connection of the guide rail with the affixing screw  55  may be made either by means of a thread-nut connection, whereby the threaded segment  580  is pushed through a through-hole in the guide rail and screwed on with a separate nut, or the threaded segment  580  is screw directly into a thread incorporated into the guide rail and thus is attached directly to the guide rail. 
     An oblong slot or an enlarged diameter of a through-hole made also be provided on the guide rail itself to provide adequate play for adjustment of the position of the guide rail. 
     Of course, it is possible to produce the seat  30  along with the curve on the guide rail  10  and to design the base part  20  or the door inner panel or the assembly carrier flat. Likewise, it is possible to produce, on both sides of the affixing screw  55 , appropriately shaped contact zones which have a curve corresponding to the respective seat of the guide rail or the base part. 
     In a variant of the invention, as depicted in FIG. 5, the seat  30  is designed as a cup-shaped recess in a conical or truncated ball-shaped projection  33 . An enlarged, unobstructed space is formed between the guide rail and the base part by means of the conical projection, thus increasing the degree of movability of the guide rail and the base part relative to each other. With such a conical or ball-shaped projection  33  with a seat  30  formed in it, it is possible to place the base part and the guide rail directly on each other. For example, the base part is equipped with a cup-shaped recess in a conical projection  33  and a ball-shaped seat is provided on the guide rail, and they are placed directly in each other. Through-holes  40 , through which a standard threaded pin is passed, are provided in both the cup-shaped recess of the base part and in the ball-shaped seat  30 . Affixing then occurs by screwing by means of affixing nuts, the heads of which are either ball-shaped, as depicted in FIG. 4, or cup-shaped. The through-holes  40  in the base part  20  and in the guide rail  10  may be designed as oblong slots which have a different orientation from the longitudinal direction. Thus, it is possible to adjust the guide rails in multiple planes. 
     FIG. 6 depicts an alternative embodiment of the invention, in which the affixing means  50  is nonreleasably connected with the guide rail  10 . The affixing means is designed here as a threaded segment  51  with a curved contact zone  52  and welded directly onto a curved projection or a passage through the guide rail  10  or nonreleasably connected with the guide rail  10  in some other manner. This produces a curved seat  30  which corresponds to a corresponding cup-shaped seat of the base part (not shown). The guide rail  10  thus preassembled can be mounted directly on the base part, which enables simplification of assembly. 
     Of course, it is also possible to connect the affixing means  50  with the base part  20  and to provide a cup-shaped seat on the guide rail. 
     FIG. 7 depicts a cross-section through a motor vehicle door with a base part  20  designed as a door module and a guide rail  10 . A seat  30  in the form of a barrel-shaped or cylindrical recess is formed on the base part  20 , in which recess a through-hole  40 , through which an affixing means  55  is passed, is formed. On the guide rail  10 , a mating part  300 , shaped as a positive impression of the seat  30 , is formed and is placed in the seat  30  for assembly of the motor vehicle door. In the example depicted, both the seat  30  and the mating part  300  are arranged or formed on the base part  20  on the upper affixing zone of the guide rail  10 . For assembly of the guide rail  10  on the base part  20 , these are placed on top of each other such that the seat  30  and the mating part  300  lie on top of each other, and then the guide rail  10  is mounted initially still tiltable around one axis but immovable relative to each other by means of an affixing means  55  designed as a screw and a sliding block  59 . In the case of a motor vehicle side door, the tilting axis is essentially parallel to the direction of travel, in rear doors accordingly perpendicular thereto. Thus, adjustability of the guide rail  10  is obtained in the so-called y-direction, which is usually essential with curved window panes, and unwanted tilting motions around the longitudinal axis of the guide rail  10  are securely braced and prevented by the barrel-shaped or cylindrical design of the seat  30  or the mating part  300 . 
     An adjustment bolt  60 , which can be set in various positions on the base part  20  by means of a check nut  60 , is affixed in the lower affixing zone of the guide rail  10 , which is indicated by the arrow A. This defines the degree of angular displacement simply and reliably. As soon as the correct adjustment of the guide rail  10  to the base part  20  has been made, the screw  55  is tightened accordingly and the sliding block  59  provided with a thread also defines the upper affixing zone. 
     Especially for stress-free affixing of nonadjustable panes, provision is made that a cylinder-cup combination is arranged in the upper affixing zone and a ball-cup combination is arranged in the lower affixing zone such that the corresponding displacement around the respective axes is possible. At least one of the affixing points is equipped with the seat  30  and its mating part  300  according to the invention; of course, different combinations of the seats or mating parts may be used.

Summary:
The invention concerns a window lifter with a guide rail ( 10 ) affixed on a base part ( 20 ) on a door inner panel, of an assembly carrier. The object of the invention is to provide a window lifter which is simple to adjust and prevents stressing of the window lifter system. This object is accomplished in that a seat ( 30 ) is formed on the base part ( 20 ), which seat is associated with a correspondingly shaped mating part ( 300 ) arranged on the guide rail ( 10 ), whereby the seat ( 30 ) and the mating part ( 300 ) are designed form-fittingly such that the guide rail ( 10 ) and the base part ( 20 ) are mounted tiltable relative to each other.