DE19811108A1 - Door hinge with lock, especially for vehicles - Google Patents

Abstract

The door hinge has a pillar bracket (5) and a door bracket (3), which are hinged to one another by a spigot, and which can be separated for installation purposes. It can be held in position using a spring element (11), which engages in notches (13) in a carrier plate (9). The door bracket has a connection to the spigot which transmits rotation, and the spigot has a similar connection to the carrier plate. The former connection may be an insertion connection, and at least one recess (17) in the door bracket may surround the external surfaces of the spigot.

Description

The present invention relates to a door hinge with fixed actuator, consisting of

• - a column console and
• - a door console,
• - The articulated with each other via a hinge pin and are separably connected for assembly,
• - The lock is a detent on a Mit slave plate engaging spring element comprises.

According to the state of the art, a door hinge is integrated system known, in which the column console consists of a Extruded section and the door bracket from a cast or Forging is formed. The articulated connection between Column console and door console takes place in one eye the column bracket rotates in its position fixed hinge pen. The hinge pin enters at one end Hinge eye of the door console and one at its other end Driver plate connected to the door console in a rotationally fixed manner is provided with catches or catch rollers. In the detents or locking rollers of the driver plate engages a spring element and keeps an open door in the preset position tions, be by the number and arrangement of the detents be true.

It is an object of the present invention to provide a door hinge of the aforementioned type while reducing production cost while increasing functional reliability to continue training.

This object is achieved in that

• - The door console rotatably with the hinge pin and
• - The hinge pin rotates with the driver plate connected is.

A door hinge according to the invention with an integrated locking device ler stands out compared to a known door hinge through out that one by moving one on the door console struck vehicle door generated torque solely by the hinge pin from the door bracket to the drive plate the lock is transmitted. In known door hinges became the tasks of articulation and moment transfer so divided that the hinge pin alone for the up taking the weight of a hinged vehicle door as well the linkage is responsible. The torque is after State of the art through the door console directly on the driver transfer plate. This kind of torque transmission will thereby achieved that the door bracket with the driver plate is rotatably connected. Resulting from vehicle vibrations in this case, however, at the junction between Door console and driver plate a relative movement, which in Contact area for excessive wear and material leakage until the lock fails. In addition, must the door bracket for torque transmission has its own lever arm be trained with driving nose. When designing also take into account that the hinge is separable should be. This door console has a very complex structure on, making the entire door hinge considerably more expensive becomes.

According to the present invention, the moments are over no longer carried by a lever arm, which is specifically for this purpose the door console must be trained, but by non-rotatable Connections from the door console over the hinge pin to the Drive plate. An additional lever arm on the door Console can thus be omitted, which saves several Work steps while simplifying the structure a door console according to the present invention.

In a preferred embodiment, the non-rotatable Ver bond between door bracket and hinge pin in the form of a Plug connection executed, in particular in that a  Recess of the column console flats on the outside of the Grips hinge pin.

The hinge pin is advantageously ge as a rotating part manufactures, so that the outside flattening in later Contact area with the column console in a simple manner Sawing or milling can be made. The recesses the door console, which receives the flats of the pivot menden or comprehensive, can also in the form of a Mä solution.

In a development of the invention, the non-rotatable Ver bond between hinge pin and drive plate also executed in the form of a plug connection, this plug connection a cross-sectional area representing a polygon having. The preferred cross-sectional area shape here Square or hexagon. One free from the hinge eye of the Column console protruding end of the hinge pin according to known methods with such a cross section provided area. The preferably manufactured as a stamped part Driver plate carries a at a corresponding point selected cross-sectional area punching and is at assembly with this punching on the one described above pushed free end of the hinge pin and then in a known manner by riveting or screwing or the like fixed in position.

The attachment of the driver plate is particularly advantageous and the simultaneous securing of the position of the hinge pin a common fixation. This fixation preferably follows in the form of a riveting.

On the opposite end of the hinge pin is in the eye of the door console is attached in a known manner. In a preferred arrangement of the elements then affects the weight by virtue of the door console and the door attached to it on the door hinge that the articulation of the two brackets  parts with the non-rotatable connection between the door console and Hinge pin ensured without additional fasteners is. To increase the functional reliability of such Door hinge in wind or dynamic loads However, a fuse is always in shape on the door console a screw connection provided. This backup is at for example in the form of a Ge arranged on the door console executed windstift, the transverse or perpendicular to the central axis of the hinge pin and either on the hinge pin engages in a knurling or in a recess.

In a preferred embodiment of an inventive Door hinge, however, is the hinge eye of the door console Through hole executed so that the security measure in Form of an axial screw on the end Hinge pins can be made.

In an advantageous development, the hinge pin carries at its end adjacent to the safety screw connection a conical tapering towards this screw connection Section. When hanging the door during assembly or maintenance work centered out in the form described he guides hinge pins in the hinge eye of the door console itself, thereby assembling a door according to the invention hinge relieved and accelerated at the same time can be.

In a preferred embodiment of the present invention The parts of known door hinges can largely un changed. However, this simplifies Structure of the door console very strong. So it will also possible, the door console also in the form of a rolled To produce extruded section, which then in simply by drilling or milling in just a few steps can be completed. So a door hinge can be used integrated lock according to the present invention while maintaining a proven constructive structure for  Increased safety through wear reduction and Simultaneous reduction in production costs through simplification important assemblies. Another is Ge weight saving through the use of aluminum as material al especially the console parts possible.

In a particularly advantageous development, the free end of the spring element rotatably arranged a roller. The integrated lock of the door hinge includes changes the spring element and the driver plate with catches, but now the latching effect by the under spring load in Detents of the driver plate or pushing them over roll roll is generated. The driver plate can thus consist of a simple stamped part. Other elements such as B. locking rollers with a supportive assembly aid and each own linkage etc. can be replaced without replacement fall.

The role itself advantageously consists of a high wear-resistant material, especially from a sintering plant material. Since the surface pressure is already integrated with known As a result, ascertainers are very high, which makes them strong claimed side surfaces of the driver plate preferably in surface hardened using an inductive process.

A determiner constructed in this way points towards known inte door locks have the advantage that it is easy overpainted or even by thermal painting process steps can be passed through. Compared to usual Baking temperatures, chemicals and paint coatings a door arrester according to the invention insensitive. Through paint blockages caused by the lock due to the high forces occurring in the locking device overcome. In normal operation, all important loading ranges of the determiner automatically from possibly disturbing Paint residues freed.  

To reduce the friction is in a training between the free end of the spring element and the roller a slide sleeve provided. It is preferably made of Teflon and will simply put over the free end of the spring element. The Teflon sliding sleeve can e.g. B. by pressing or turning inside out be secured axially after attaching the roller. Under Realization of the measures described below can however, such a fixation can be dispensed with by building in this or a similar way good and durable plain bearing of the role on the Teflon sleeve attached to the end of the spring element becomes.

In one development, the role has one or both End areas with respect to their axis of rotation or center axis because a collar, or a groove in its middle area on. Secures itself in resilient contact with the driver plate the role thus automatically itself, so that of further measure axially secured the Teflon sliding sleeve as well as the Role can be disregarded. In addition, one can work together play with the driver plate on the end of the spring element role within production that can be moved within limits actively adapt to tolerances of the components of the door hinge.

A roller with a groove in the central region is preferred the role used. The width of the groove is more advantageous Specified by the thickness of the driver plate to each axial displacement of the roller or the sliding sleeve on the to prevent the free end of the spring element.

The use of an oil-soaked sin is particularly advantageous termaterials as material for the role. This is then in addition to a simple structure also the lock under one set a minimized number of individual parts of it completely maintenance-free lock can be manufactured. In particular, the with known locks, the usual greasing in contact area of a free spring end and a driver plate  remain under.

The groove of the roller can advantageously be in the contact area be coated or overmolded with the driver plate. Be A plastic is preferably used for this. Through this The measure can be vibration or resonance appearances in the vehicle are dampened or even prevented become.

A door hinge according to the invention is therefore in total in the Assembly can be easily separated after painting final assembly does not have to be readjusted. Due to the compact design with the integrated door retainer Advantageously, there is no need for an additional door strap can be seen because the door stop has an end stop points. This allows additional articulation points on the chassis and the doors are eliminated, as is the door retaining strap as a single part himself. A door hinge according to the invention can be used the structure of the lock described above fully constantly maintenance-free and insensitive to paints become.

Below are preferred embodiments of the invention described with reference to the drawing. The pictures show in

Fig. 1 is a side view of a first embodiment of a secured by a transverse to the axis of rotation screwing door hinge with integrated fixed actuator in the closed state;

Fig. 2 is a perspective view of the door hinge of Fig. 1;

Fig. 3 is a side view of the door hinge of Figure 1 in the open state.

FIG. 4 shows a section through FIG. 3 in a plane AA;

Fig. 5 is a perspective view of a door bracket according to the embodiment of Fig. 1;

. Figs. 6a and 6b is a side view of a hinge pin of the embodiment of Figure 1 and a perspective view of such a hinge pin in accordance with;

Figure 7 is a side view of a further embodiment of a door hinge with an integrated door retainer in the closed state, showing the axial securing device selected here.

Fig. 8 is a perspective view of the embodiment of Fig. 7;

FIG. 9 shows a side view of the door hinge from FIG. 7 in the open state;

Fig. 10 is a sectional view through the area of the coulter nieraugen of Fig. 9;

FIG. 11 is a perspective view of a door panel according to the embodiment of FIG. 7;

FIG. 12a and 12b is a perspective view of a Scharnierzap fens according to the embodiment of Figure 9 with a side view.

Fig. 13 is a perspective view of the door hinge of Fig. 7 and Fig. 8 with an alternative embodiment form of a lock and

Fig. 14 a and 14b are views of FIG. 13 each lenkonsole omitting säu.

Fig. 1 shows a first embodiment of a door hinge 1 with integrated lock 2 in the closed state. From the side view of FIG. 1, the structure of the door hinge of a door panel 3 and a door below the bracket 3 is arranged in the region of a hinge pin 4 goes Säulenkonso le forth. 5 The hinge pin 4 can only be seen in the small area of a shoulder 6 , since it is closed above and below by the hinge eyes 7 , 8 of the brackets 3 and 5 . Below the hinge eye 7 of the door bracket 3 , a driver plate 9 of the lock 2 with the coulter pin 4 is rotatably connected via a rivet connection 10 , as will be described with reference to FIG. 4. An S-shaped spring element 11 is fastened in the column bracket 5 and engages with a free end 12 as part of the arrester 2 in detents 13 of the driver plate 9 .

Above paragraph 6 , a fuse 14 in the form of a screw 15 is arranged on the door bracket 3 , which prevents accidental separation of the door hinge 1 after the gene gene. The screw 15 engages transversely to the axis of rotation in a certain area of the hinge pin through the hinge 4, an eye 7 of the door panel 3, which is illustrated with reference to FIGS. 6 and 7.

The paragraph 6 of the hinge pin 4 forms together with the hinge eye 8 of the door bracket 3 by two lateral Abfla corrections 16 , which are enclosed by a corresponding recess 17 of the door bracket 3 , a non-rotatable plug connec tion. The door hinge 1 after loosening the secure screw 15 is easy to dismantle in assembly or for maintenance in two parts.

Fig. 2 shows a perspective view of the door hinge of Fig. 1 with a particularly clear representation of the S-shaped course of the spring element 11 from the column bracket 5 to the lock 2 or the detents 13 of the drive plate 9th The lock 2 is connected to the door bracket 3 via the hinge pin 4 , of which only the paragraph 6 is visible in this illustration. The paragraph 6 is from savings 17 of the hinge eye 8 of the door bracket 3 umschlos sen, so that there is a non-rotatable connection by simply plugging the hinge pin 4 until reaching paragraph 6 in the door bracket 3 .

FIG. 3 is a side view of the door hinge 1 of FIG. 1 in the open state from the position of an open door. On the basis of the visible in this illustration two fastening supply points 18 per console 3 , 5 , the compact structure of the actual articulated connection and the integrated door lock 2 by the hinge pin 4 is clear.

Fig. 4 is a sectional view of a plane AA through Fig. 3, through which the internal structure of the linkage or torque transmission around the hinge pin 4 is illustrated. The hinge pin 4 runs with a cylindrical part 19 through the hinge eye 7 of the column bracket 5 . At its upper end with respect to the insert position, the cylindrical section 19 is delimited by the shoulder 6 , which has a larger diameter than the cylindrical section 19 and thus represents a one-sided positional securing of the hinge pin 4 . At the opposite end, the hinge pin 4 runs into a polygonal connector 20 , onto which the slave plate 9 is pushed together with an assembly support 21 for torque transmission that is fixed in terms of rotation. Between the mounting bracket 21 and the driver plate 20 , the number of locking positions correspondingly many locking rollers 22 are net angeord, between which the free end 12 of the spring element 11 engages resiliently. Below the mounting bracket 21 , the hinge pin 4 runs out into a rivet bolt 23 with a clear reduction in cross section. Thus, the entire arrangement can be fixed in position by simply plugging into one another via a single attachment in the form of riveting the rivet bolt 23 in a single work step. If necessary, the riveting can also be replaced by a screw connection. In any case, the receiving opening in the driver plate 9 and the mounting bracket 20 is covered by a disk 24 for securing the position.

Above paragraph 6 , the hinge pin 4 runs out into a further cylindrical section 25 which is received in the hinge eye 8 of the door bracket 3 . This area is also fixed to secure the door hinge 1 with the United screw 15 perpendicular to the central axis of the hinge pin 4 through the hinge eye 8 .

FIG. 5 shows a perspective view of the door bracket 3 of the embodiment from FIG. 1. In the present case, the hinge eye 8 is designed as a blind hole, as has already been shown with reference to FIG. 4. A threaded hole 15 a is arranged perpendicular to the central axis of the hinge eye 8 to secure the door hinge against unintentional separation. At its lower end, the door bracket 3 has recesses 17 arranged symmetrically to the central axis of the hinge eye 8 , which in the present case can be realized particularly simply by milling. Furthermore, the door bracket 3 also comprises two fastening points 18 for attaching the vehicle door.

Fig. 6a shows the hinge pin 4 of the first game Ausführungsbei from Figs. 1-5 in a plan view, Fig. 6b he completes the representation of Fig. 6a in the form of a perspective representation's hinge pin 4th As already explained with reference to FIG. 4, the hinge pin 4 builds from its upper to the lower end from the cylindrical section 25 , the paragraph 6 , the cylindrical section 19 , the connecting piece 20 and the rivet bolt 23 . Between the individual sections, construction or manufacturing-related transition areas, for example radii, can be arranged. The hinge pin 4 can be made in one piece as a turned part in post-processing by milling to produce the flat 16 and a polygonal cross-section in the area of the connec tion piece 20 .

Fig. 6b shows that the cylindrical portion 25 also has an additional flattening or recess 25 a. In the present embodiment, the screw connection 15 engages through this hinge eye 8 on this recess 25 a, in order thereby to produce a clamping connection between the door bracket 3 and the hinge pin 4 as a safety measure.

Fig. 7 shows a side view of a further embodiment of a door hinge 1 with an integrated door lock 2nd Analogously to FIG. 1, the closed state of the door hinge is also shown here. The difference between the embodiments of Fig. 1 and Fig. 7 is significantly that in the embodiment of FIG. 7, an axial Ver screw 26 takes the place of the screw 15 transversely to the central axis of the hinge pin 4 .

FIG. 8 shows the embodiments of FIG. 7 in a perspective view, the structural changes in the area of the door console 3 which are only hinted at in FIG. 7 being better recognizable. A comparison between FIGS. 8 and 2 already shows that the arrester 2 , the column bracket 5 and the spring element 11 remain unchanged.

To illustrate the changes, the second embodiment is shown in the open state, as in FIG. 9, analogously to FIG. 3. Here again in a plane AA through the hinge eye 8 of the door bracket 3 , the hinge pin 4 , the hinge eye 7 of the column bracket 5 and the locking device 2 .

FIG. 10 shows this sectional illustration in the plane AA from FIG. 9 again. A comparison with Fig. 4 shows that in Fig. 10 the structure below the paragraph 6 of the hinge pin 4, no changes were made. Above the shoulder 6 , the hinge pin 4 runs out into a cylindrical end piece 28 via a conical region 27 . Parallel to the central axis of the hinge pin 4 , the sections 27 and 28 are penetrated by a blind bore with an internal thread. In this blind hole engages a screw 29 , which also has a conical section 30 between the head part and the threaded part. The hinge eye 8 is adapted to this embodiment, by correspondingly expanding the opening for receiving the hinge pin 4 in the conical shape of the hinge pin 4 in the region 27 in the lower region of the through bore. At the opposite end, a cylindrical widening 31 is provided for lowering the head of the screw 29 and for better fixing the axial screw connection 26 .

Fig. 11 shows the door bracket 3 of the embodiment of Fig. 7 in analogy to the representation of Fig. 5. In the outer Ver without a sectional view, the two door consoles differ in particular in that at the lower end of the hinge eye 8 near the recesses 17 one conical Wei device 27 a is provided. All other design changes shown in FIG. 10 are hidden in the illustration of FIG. 11.

In FIGS. 12a and 12b of the hinge pin 4 is shown the second embodiment in a plan view and in a perspektivi rule representation. The comparison between Fig. 6a and Fig. 12a shows only slight deviations of the two embodiments with respect to the paragraph 6 , the cylindrical part 19 , the connecting piece 20 and the rivet bolt 23rd The part of the hinge pin 4 , however, has undergone significant changes above the paragraph 6 . Here, the conical section 27 with the subsequent cylindrical end piece 28 are new compared to the first embodiment. While in Fig. 6a at the upper end only a center hole is introduced, the second embodiment of the hinge pin 4 carries in this area from the upper end to the paragraph 6 parallel to the central axis of the rotating part a blind hole with internal thread.

Fig. 12b illustrates in perspective the sequence of the individual elements of the hinge pin 4 , wherein the already recognizable from Fig. 10 separation between the moment transfer through the flats 16 with the recesses gene 17 and the self-centering through the conical section 27 with the counterpart of conical extension 27 a in the hinge eye 8 stand out. Compared to alternative approaches, this embodiment is particularly characterized in that very high moments can be transmitted through the perpendicular or parallel to the axis of rotation interfaces between the surfaces 16 and 17 without force components, for example, can result in the direction of the axis of rotation. At the same time centering operates 27/27 at a Zusaummenfü of the door hinge gen automatically and, in conjunction with the conical portion 30 to the screw 29 of the axial screw 26 to a safe and quick assembly.

Fig. 13 shows a perspective view of the door hinge 1 of Fig. 7 and Fig. 8 with an alternative embodiment of a lock 2 from the inside of the car. The articulation of the door bracket 3 on the column bracket 5 has remained unchanged. In contrast to the representations of FIGS. 1-4, the free end 12 of the S-shaped Federelemen tes 11 now carries a roller 32nd The roller 32 is rotatably arranged over the free end 12 of the spring element 11 . To improve their rolling properties, a sliding sleeve made of Teflon is arranged between the roller 32 and the free end 12 of the spring element 11 , which is not shown further.

A special structure with end-side frets 33 results in a groove 34 in the central region of the roller 32 , the width of which is adapted to the thickness of the driving plate 9 . The driver plate 9 itself is formed by a simple stamped part, this part of the arrester 2, in particular in comparison to the illustration in FIG. 4, no longer has latching rollers with corresponding support and holding devices. However, the driver plate 9 also has a surface that is continuously profiled by detents 13 . In this area, it is always under spring pressure in contact with the groove 34 of the roller 32 . This part of the total surface of the driver plate 9 is therefore surface-coated in an inductive hardening process.

To protect the roller 32 itself against wear, it is made of a highly wear-resistant sintered material that is additionally oil-soaked. The lock is correspondingly self-lubricating in the very wear-prone contact area between the spring element 11 or intermediate elements and the driver plate 9 . Through this permanent lubrication together with the choice of a sintered material of the roller 32 and the surface coating of the driver plate 9 , the maintenance-free locking device 2 achieves a high overall service life that exceeds the comparable locking device.

Fig. 14a and 14b are a perspective view and a plan view of FIG. 13 illustrates, for clarity of the construction of each omitting column bracket 5. In this illustrated Fig. 14a, the transmission of a torque of the door panel 3 by the shoulder 6 on the hinge pin 4 participants to the plate 9 with the fixed plate 2, which in turn is rotated against the spring force acted on by roll 32.

Fig. 14b shows a plan view of the closed door hinge kidney 1 in the representation of Fig. 14a. In this illustration, the partial overlap of the driver plate 9 by the upper collar 33 of the roller 32 is particularly clear, which is only recognizable in the illustration of FIG. 14a. The lower collar of the roller 32 , which is not further visible, covers the driver plate 9 accordingly, so that the roller 32 is secured axially on the free end 12 of the spring element 11 with resilient contact with the driver plate 9 in the region of the groove 34 .

Furthermore, it can be seen from the center axes of the spring element 11 with the angular rejection between the two parts of the S-shaped curved spring element 11 that the lock 2 is under spring tension even in the closed hinge position. The lock 2 is thus always under spring force, the individual components being in contact with one another at all times. There is thus no play in particular in the area of the roller 32 , which could lead to undesirable noise developments in the case of vibrations in the vehicle. Nevertheless, the roller 32 in the area of its groove 34 can also be used as a preventive damping measure z. B. with a thermally stable and insensitive to high surface pressures plastic coating, which is not shown in Fig. 14a, 14b.

In addition, a vehicle door struck on the door bracket 3 is held in its closed position by the spring force of the arrester 2 . Accordingly, the closing process is supported in a desired manner after overcoming the detents 13 . Upon reaching the first of the detents 13 in the slave plate 9 , the hinge 1 is then securely secured against an unintentional slamming of a vehicle door hinged on the door bracket.

Claims (15)

1. Door hinge with lock, consisting of

• - a column console and
• - a door console,
• - which are articulated with one another via a hinge pin and are separable for assembly,
• - The lock comprises a spring element engaging in detents on a slave plate, characterized in that
• - The door bracket ( 3 ) rotatably with the hinge pin ( 4 ) and
• - The hinge pin ( 4 ) is rotatably connected to the driver plate ( 9 ).

2. Door hinge according to claim 1, characterized in that the non-rotatable connection between the door bracket ( 3 ) and the hinge pin ( 4 ) leads in the form of a plug connection, in particular in that at least one recess ( 17 ) of the door bracket ( 3 ) flats from the outside ( 16 ) of the hinge pin ( 4 ). 3. Door hinge according to one of claims 1 and 2, characterized in that the non-rotatable connection between the hinge pin ( 4 ) and driving plate ( 9 ) is designed in the form of a plug connection, this plug connection has a polygonal cross-sectional area, preferably in the form a square or a hexagon. 4. Door hinge according to one of claims 1 to 3, characterized in that the fastening of the driver plate ( 9 ) and the position securing of the hinge pin ( 4 ) are carried out via a common fixation, preferably in the form of riveting. 5. Door hinge according to one of claims 1 to 4, characterized in that on the door bracket ( 3 ) a fuse in the form of a screw ( 15 ) is arranged, which runs through the door bracket ( 3 ) to the hinge pin ( 4 ) and there in a Knurling, a recess ( 25 a), or engages in a threaded bore ( 15 a). 6. Door hinge according to claim 5, characterized in that the screw connection ( 15 ) runs in the direction of the central axis of the hinge pin ( 4 ). 7. Door hinge according to one of claims 5 and 6, characterized in that the hinge eye ( 8 ) of the door bracket ( 3 ) is designed as a through hole and the hedging tion in the form of an axially arranged Ver screw ( 26 ) on the hinge pin ( 4 ) he follows. 8. Door hinge according to one of claims 1 to 7, characterized in that the hinge pin ( 4 ) has at its, the fuse adjacent end to the United screwing ( 26 ) tapered conical section ( 27 ). 9. Door hinge according to one or more of the preceding claims, characterized in that column bracket ( 5 ) and door bracket ( 3 ) in the form of rolled Profilstrangab cuts are made, which then z. B. be further processed by drilling or milling. 10. Door hinge according to one or more of the preceding claims, characterized in that at the free end ( 12 ) of the spring element ( 11 ) a roller ( 32 ) made of wear-resistant material, in particular of a sintered material, is rotatably arranged. 11. Door hinge according to claim 10, characterized in that a sliding sleeve is arranged between the free end ( 12 ) of the spring element ( 11 ) and the roller ( 32 ). 12. Door hinge according to claim 10 or 11, characterized in that the roller ( 32 ) at one or both end areas each with respect to its axis of rotation a collar ( 33 ), or a groove ( 34 ) in its central region. 13. Door hinge according to one or more of the preceding claims 10-12, characterized in that the width of the groove ( 34 ) is predetermined by the thickness of the driver plate ( 9 ). 14. Door hinge according to one or more of the preceding claims 10-13, characterized in that the material of the roller ( 32 ) is an oil-soaked sintered material. 15. Door hinge according to one or more of the preceding claims 10-14, characterized in that the groove ( 34 ) is coated in the contact area with the driver plate ( 9 ), in particular with a plastic.