The invention concerns a torque transmission device in the drive train of a motor vehicle to transmit torque between a drive unit, especially an internal combustion engine, with a drive shaft, especially a crankshaft, and a transmission with at least two transmission input shafts that are tightly connected to a clutch disc having a friction lining, and there is an intermediate pressure plate between the friction linings of one clutch disc and the friction linings of the other clutch disc that is tightly connected to the drive shaft of the drive unit, whereby the friction lining of the clutch discs are between the intermediate pressure plate and the pressure plates that move axially with the assistance of an actuation device relative to the intermediate pressure plate in reference to the transmission input shafts in order to hold the friction linings between the intermediate pressure plate and the pressure plates.
The two clutch disks and the interacting pressure plates form a double clutch. In conventional torque transmission devices with a double clutch, the double clutch bearing system is frequently complicated.
The task of the invention is to create a torque transmission device according to the preamble of claim 1 by means of which the double clutch bearing system is improved.
The task is solved in that the intermediate plate is radially mounted on at least one of the transmission input shafts of a torque transmission device in the drive train of a motor vehicle to transmit torque between a drive unit, especially an internal combustion engine, with a drive shaft, especially a crankshaft, and a transmission with at least two transmission input shafts that are tightly connected to a clutch disc having a friction lining, and there is an intermediate pressure plate between the friction lining of one clutch disc and the friction lining of the other clutch disc that is tightly connected to the drive shaft of the drive unit, whereby the friction lining of the clutch discs are between the intermediate pressure plate and the pressure plates that move axially with the assistance of an actuation device relative to the intermediate pressure plate in reference to the transmission input shafts in order to hold the friction linings between the intermediate pressure plate and the pressure plates. This creates a rigid and compact bearing system for the double clutch. The intermediate pressure plate can be directly or indirectly mounted on one of the transmission input shafts, for example via an essentially tubular hub.
One preferred exemplary embodiment of the torque transmission device is characterized in that the intermediate pressure plate is mounted on one of the transmission input shafts with the assistance of a bearing device (especially a radial bearing) especially on an internally hollow transmission input shaft in which an additional transmission input shaft is rotatably mounted. The bearing can for example be a rolling bearing or a journal bearing.
Another preferred exemplary embodiment of the torque transmission device is characterized in that one of the clutch discs is releasably affixed (i.e., removable without destroying it) to one of the transmission input shafts, especially on the additional transmission input shaft. The bearing for the intermediate pressure plate is for example a support bearing that is shoved onto a bearing seat on the hollow transmission input shaft during assembly of the double clutch and is axially fixed with a snap ring. Then one of the clutch discs is affixed to the additional gear input shaft.
Another preferred exemplary embodiment of the torque transmission device is characterized in that the clutch disc affixed to one of the transmission input shafts, especially to the additional transmission input shaft, has a two-part design. The motor-side clutch disc affixed to the additional transmission input shaft prevents access to the snap ring. The two-part design makes it easier to access the bearing of the intermediate pressure plate.
Another preferred exemplary embodiment of the torque transmission device is characterized in that the clutch disc affixed to one of the transmission input shafts, especially to the additional transmission input shaft, has a hub from which an inner flanged ring proceeds that is releasably affixed, i.e., removable without destroying it, to an outer flanged ring on which the friction linings are mounted radially to the outside. The radial outside flanged ring is preferably installed in the double clutch on the transmission side during assembly. The radial inner flanged ring with the hub is loosely placed on the double clutch and only mounted after affixing the snap ring.
Another preferred exemplary embodiment of the torque transmission device is characterized in that the two flanged rings are connected by at least one screw connection. The two flanged parts are advantageously centered by means of a centering seat. The two flanged rings can for example be keyed with each other via splines. For example, the two flanged parts or flanged rings are releasably connected by at least one snap connection.
Another preferred exemplary embodiment of the torque transmission device is characterized in that one of the gear input shafts is designed as a hollow shaft in which the additional transmission input shaft is rotatably mounted, whereby an essentially tubular hub is rotatably mounted between the two transmission input shafts with a drive-side and a transmission-side end, and the intermediate pressure plate is affixed to the drive-side of the hub. It is preferably affixed by rivets. The intermediate pressure plate can also be affixed to the hub by flanging or with a centering seat with a snap ring.
Other preferred exemplary embodiments of the torque transmission device are characterized in that the gear-side end of the hub within the hollow shaft is mounted in the hollow shaft, on the hollow shaft or on the additional transmission input shaft. The bearing can be a rolling bearing, preferably a needle bearing, or a journal bearing. For lubrication, the bearing can be connected with the oil chamber of the transmission, or with its own independently sealed grease lubrication system. The rigidity of the bearing is preferably such that the natural relaxation vibration of the of the first order lies above the driving mode.
Another preferred exemplary embodiment of the torque transmission device is characterized in that the intermediate pressure plate is supported in an axial direction on one of the transmission input shafts. The axial control forces of the double clutch are thereby no longer transmitted to the crankshaft.
Another preferred exemplary embodiment of the torque transmission device is characterized in that the double clutch is pre-mounted in a clutch housing. The clutch housing is also termed the bell housing. The accessibility of the pre-mounting points is for example enabled by corresponding accesses in the drive-side clutch disc of the double clutch.
Another preferred exemplary embodiment of the torque transmission device is characterized in that the bearing site of the pre-mounted double clutch is around or close to the center of gravity of the double clutch. This arrangement of the bearing site or bearing device of the intermediate pressure plate makes it easier to mount and transport the pre-mounted double clutch.
Another preferred exemplary embodiment of the torque transmission device is characterized in that one of the transmission input shafts is designed as a hollow shaft in which the additional transmission input shaft is rotatably mounted, whereby the intermediate pressure plate is mounted via a bearing device directly on one of the transmission input shafts, especially the additional transmission input shaft. An additional pilot bearing can be provided for the additional transmission input shaft in the drive shaft on the drive-side end of the additional transmission input shaft.
Another preferred exemplary embodiment of the torque transmission device is characterized in that one of the transmission input shafts is designed as a hollow shaft in which the additional transmission input shaft is rotatably mounted, whereby the intermediate pressure plate is mounted via a bearing device to a hub bearing that is a releasably affixed, i.e. removable without destroying it, to the drive-side end of the additional transmission input shaft. The hub bearing is affixed for example using a screw that is screwed into a corresponding threaded hole in the drive-side end of the additional transmission input shaft.
Another preferred exemplary embodiment of the torque transmission device is characterized in that one of the clutch discs is tightly connected to the hub bearing. The hub bearing enables both clutch discs to have the same hub geometry. An additional pilot bearing can be provided for the additional transmission input shaft in the drive shaft on the drive-side end of the hub bearing.
Another preferred exemplary embodiment of the torque transmission device is characterized in that the bearing device comprises a bearing outer race that is radially affixed to the inside of the intermediate pressure plate, and/or a bearing inner race that is radially affixed to the outside of the associated bearing input shaft. The bearing device is preferably designed as an angular contact ball bearing, for example an annular ball bearing. The bearing outer race can also be integrated in the intermediate pressure plate. Rolling bearings are disposed between the bearing outer race and bearing inner race in a familiar manner.
Another preferred exemplary embodiment of the torque transmission device is characterized in that the bearing inner race has a bearing section that is shoved radially inward onto one of the transmission input shafts so that the transmission-side end of the bearing section lies on a step formed on the associated transmission input shaft. The bearing section essentially has the same shape as a circular cylinder jacket. Radially to the outside, the bearing section forms a contact surface for the rolling bearings of the bearing device. Instead of the step, a snap ring can be axially affixed to the associated transmission input shaft.
Another preferred exemplary embodiment of the torque transmission device is characterized in that an attachment section proceeds from the drive-side end of the bearing section to which a retaining ring is releasably affixed (i.e., removable without destroying it). The attachment section essentially extends in a radial direction. The retention ring is preferably affixed by means of at least one screw connection to the attachment section.
Another preferred exemplary embodiment of the torque transmission device is characterized in that the retention ring is fixed with the aid of a screw connection to the attachment section of the bearing inner race. The screw connection is accessible during assembly, for example through a corresponding opening in the associated drive-side clutch disc.
Another preferred exemplary embodiment of the torque transmission device is characterized in that the retention ring has a fixing section radially on the inside that exerts a closing force on the locking ring depending on the status of the screw connection, and the force causes the locking ring to engage in an annular groove that is provided in the associated transmission input shaft. This makes it easy to axially affix the bearing device on the associated transmission input shaft.
Another preferred exemplary embodiment of the torque transmission device is characterized in that the locking ring is slotted and pretensioned so that it can be shoved onto the associated transmission input shaft. Only when the screw is tight is the pretension of the locking ring overcome so that it is axially fixed in the annular groove.
Another preferred exemplary embodiment of the torque transmission device is characterized in that the bearing outer race, the bearing inner race, the retention ring and/or the locking ring are made of sheet metal. This can reduce manufacturing costs.
Another preferred exemplary embodiment of the torque transmission device is characterized in that there is a torsional vibration damper between the drive shaft of the drive unit and the double clutch, especially a dual-mass fly wheel comprising a damper input part that is firmly affixed to the drive shaft of the drive unit, and a damper output part that is releasably attached (i.e., removable without destroying it) to a double clutch housing part to which the intermediate pressure plate is affixed. The releasable connection is preferably a keyed axial plug-in connection, especially with complementary splines. The input part of the vibration damper is centered on the crankshaft. The double clutch is centered on one of the transmission shafts. Any offset in a radial direction can be at the contact site between the output part of the vibration damper and the energy storage mechanisms, especially bow springs of the vibration damper. The plug-in connection preferably designed as spline toothing ensures sufficient axial mobility of the double clutch relative to the vibration damper. This makes assembly easier. The primary parts or input parts of the vibration damper can be pre-mounted on the crankshaft. In addition, axial vibrations of the crankshaft that arise during operation are not transmitted to the clutch.
Another preferred exemplary embodiment of the torque transmission device is characterized in that there is a spring device between the double clutch housing part and the damper output part; the spring device presses the damper output part against a friction/sliding device that is between the damper input part and the damper output part. The spring device is preferably a diaphragm spring. The friction/sliding device is either attached to the damper input part, or the damper output part.
Another preferred exemplary embodiment of the torque transmission device is characterized in that the damper output part has a recess to receive a section of the double clutch housing part on its inside radially within the friction/sliding device. This produces a stable, non-rotating connection between the parts connected by the plug-in connection.
Another preferred exemplary embodiment of the torque transmission device is characterized in that the double clutch housing part is made of sheet metal and has a flanged area that serves to fasten the double clutch housing part to the intermediate pressure plate. The flanged area preferably has several feet with through-holes for fasteners such as screws or rivets.
Another preferred exemplary embodiment of the torque transmission device is characterized in that the double clutch housing part has an external spline section that is designed as a single piece with the flanged area and is complementary to an internal spline that extend radially inward on the damper output part. The complementary splines easily create a nonrotating plug-in connection between the double clutch housing part and the output part of the vibration damper.
Another preferred embodiment of the torque transmission device is characterized in that the section with the external spline lies between the inner diameter and the outer diameter of the friction lining of the neighboring clutch disc. This arrangement has proven to be advantageous within the framework of the present invention.
Another preferred embodiment of the torque transmission device is characterized in that there is a reinforcing edge on the double clutch housing part radially within the external spline area. Inner reinforcement can be alternately provided by inserting another part.
Another preferred exemplary embodiment of the torque transmission device is characterized in that the damper output part is essentially shaped like an annular disc made of sheet metal on which there is a radial internal spline and at least one radial outside catch finger or arm that engages in an energy storage mechanism of the vibration damper. The internal spline can be continuous. The internal spline can also have sections without teeth to provide peripheral reinforcement and improve the deformation behavior of the double clutch housing part. The damper output part can consist of one or a plurality of parts.
Another preferred exemplary embodiment of the torque transmission device is characterized in that two catch fingers or catch arms are diametrically opposed radially on the outside of the damper output part. This ensures that the torsional vibration damper functions sufficiently.
Another preferred exemplary embodiment of the torque transmission device is characterized in that there are radial slots near the catch fingers in the damper output part. The slots serve to make the output part elastic. This makes it possible to pretension the connection between the damper output part and the double clutch housing part when assembled.
Additional advantages, features and details of the invention are found in the following description in which various exemplary embodiments are described in detail with reference to the drawings. The features cited in the claims and in the description may be essential to the invention by themselves or in any combination thereof. The following is shown in the drawings:
The crankshaft 4 of the internal combustion engine 3 is tightly connected via screw connections 9, 10 to an input part 11 of the torsional vibration damper 8. The input part 11 of the torsional vibration damper 8 is essentially shaped like a radially-extending annular disc that forms a vibration damper cage radially to the outside. A starter ring gear 12 is attached radially to the outside of the input part 11. At least one energy storage mechanism, especially a spring device 16, is at least partially held by the vibration damper cage. An output part 18 of the vibration damper 8 engages in the spring device 16. A slide ring/friction ring 19 is in between the input part 11 and the output part 18, and the ring is affixed to the input part 11. Between the output part 18 and a clutch housing part 22, is a pretensioned diaphragm spring 20 to press the output part 18 of the torsional vibration damper 8 against the slide ring/friction ring 19.
Radially to the inside, the output part 18 of the torsional vibration damper 8 is releasably attached (i.e. can be removed without being destroyed) to the clutch housing part 22. An intermediate pressure plate 26 is affixed to the clutch housing part 22 with the aid of rivets, of which only one rivet connection 24 can be seen in the sectional view. On the drive side, friction linings 29 of a first clutch disc 31 can be clamped between the intermediate pressure plate 26 and a pressure plate 28. The first clutch disc 31 is tightly held via a hub 33 to a first transmission input shaft 35 that is designed as a solid shaft. The first in transmission input shaft 35 is rotatably mounted in a second transmission input shaft 36 that is designed as a hollow shaft. A hub 38 is rotatably mounted on the drive-side end of the second transmission input shaft 36 with the aid of a rolling bearing 37, and the intermediate pressure plate 26 is radially affixed to the outside of the hub. On the transmission side, friction linings 40 of a second clutch disc 42 can be clamped between the intermediate pressure plate 26 and a pressure plate 39. The second clutch disc 42 is firmly connected via a hub 43 to a second transmission input shaft 36.
The double clutch 6 has a clutch housing 44 to which the pressure plates 28, 39 are mounted to prevent rotation but enable axial movement. In addition, the intermediate pressure plate 26 is affixed to the clutch housing 44. The clutch housing 44 is connected to the crankshaft 4 via the clutch housing part 22 and the torsional vibration damper 8. The double clutch 6 is actuated in a familiar matter via the actuation devices 46, 47 that interact with actuating levers 48, 49.
On the drive side, friction linings 89 of a first clutch disc 91 can be clamped between the intermediate pressure plate 78 and a pressure plate 88. The first clutch disc 91 with an intermediate torsional vibration damper 92 is coupled to a hub 93 that is tightly connected to a first gear box input shaft 95. The first transmission input shaft 95 is designed as a solid shaft and is rotatably mounted in a second transmission input shaft 96 that is designed as a hollow shaft.
A tubular hub 98 is rotatably mounted on the first transmission input shaft 95 by means of a needle bearing 97. The tubular hub 98 is between the two transmission input shafts 95 and 96. On the drive side, the tubular hub 98 has a conically expanding area to which the intermediate pressure plate 78 is radially affixed on the outside by means of rivets 99.
On the transmission side, friction linings 101 of a second clutch disc 102 can be held between the intermediate pressure plate 78 and a pressure plate 100. The second clutch disc 102 is coupled via a torsional vibration damper 103 to a hub 104 that is tightly connected to the second gear box input shaft 96.
The two pressure plates 88 and 100 can move axially in a familiar matter with the aid of actuating devices 106, 107 and actuating levers 108, 109 relative to the intermediate pressure plate 78. The crankshaft 64 transfers torque to and is born by double clutch 66 via the driven plate 73 and the flex plate 70. The tubular hub 98 is disposed radially between the two transmission input shafts 95 and 96 of the double clutch gear box.
The exemplary embodiment shown in
In the exemplary embodiment shown in
In the exemplary embodiment in FIGS. 1 to 5, the engagement force braces against the crankshaft when the double clutch is actuated. To increase the rigidity, the driven plate 73 in the exemplary embodiments in
In regard to the basic design and function of the damper 154 that in this instance is a component of the so-called dual-mass flywheel or forms a dual-mass flywheel, we refer to DE OS 197 28 422, DE OS 195 22 718, DE OS 41 22 333, DE OS 41 17 582 and DE-OS 41 17 579. The damper 154 possesses an input part 155 that is tightly connected via radial inner sections to the crankshaft 151, for example by means of screws 156. The input part 155 is formed by a shaped sheet-metal part that bears another component 157 radially on the outside which is also a shaped sheet-metal part in this instance. The two components 155 and 157 border an annular chamber 158 in which are held at least the energy storage mechanisms (helical springs 159 in this instance) of at least one damper. The chamber 158 is preferably sealed at least radially to the outside and contains at least a small quantity of a viscous medium that preferably is a lubricant. The torque introduced by the crankshaft 151 into the clutch assembly 140 is transferred via the input part 155, 157 to the energy storage mechanism 159 and conducted from there via an output part 160 also engaging the energy storage mechanisms 159 to the double clutch 150. The output part 160 is formed by a flange-like component that radially engages in the inside of the chamber and interacts via arms or fingers 161 with the end areas of the energy storage mechanisms 159.
A slide ring/friction ring 163 is between the input part 155 and the output part 160, and the ring is affixed to the input part 155. Between the output part 160 and the component 157, there is a pretensioned diaphragm spring 164 so that the output part 160 of the torsional vibration damper 154 is pressed against the slide ring/friction ring 163.
Radially to the inside, the output part 160 of the torsional vibration damper 154 is equipped with an internal spline 166. The internal spline 166 of the output part 160 is complementary with the external spline 167 that is on a clutch housing part 168. The spline is designed so that the torsional vibration damper 154 with the output part 160 can be shoved onto the coupling housing part 168 in an axial direction. The coupling housing part 168 is connected to an intermediate pressure plate 170 by the connections 169, of which only one rivet connection is shown in the sectional view in
The solid shaft 172 that is also termed the first transmission input shaft is rotatably mounted in the second transmission input shaft 153 designed as a hollow shaft. A hub 178 to which a second to clutch disc 179 is attached radially on the outside is rotatably mounted on the drive-side end of the second transmission input shaft 153. Radially affixed to the outside of the second clutch disc 179 are friction linings 180 that can be clamped between the intermediate pressure plate 170 and the pressure plate 171.
The transmission shaft 152 designed as a solid shaft has a shaft section 181 between hub part 175 and hub part 178 on which a bearing device 183 is mounted for the intermediate pressure plate 170. The bearing device 183 comprises a bearing outer race 184 that is affixed radially on the inside of the intermediate pressure plate 170, and a bearing inner race 185 that lies radially on the outside of shaft section 181. Rolling bodies 186 in the form of balls or rollers are between the bearing inner race 185 and the bearing outer race 184. The bearing inner race 185 is axially fixed by snap rings 188, 189 that fit in corresponding grooves of the solid shaft 152. The snap ring 189 is slotted and is also termed a locking ring. A retention ring 191 is radially affixed to the outside of the bearing inner race 185 by a screw 190; the retention ring holds the locking ring 189 in an associated ring groove in the solid shaft 152.
The transmission input shafts 152, 153 are equipped with helical teeth at the transmission side that enable the absorption of axial force. According to a feature of the invention, the output part 160 of the dual-mass flywheel 154 is not centered by an additional bearing. According to another feature of the invention, the bearing device 183 is at or near the center of gravity of the double clutch 150. This provides stable support for the double clutch 150 during transportation and assembly.
The double clutch 150 has a clutch housing 194 to which the intermediate pressure plate 170 is attached. The pressure plates 171, 172 are fixed to the clutch housing 194 in a manner that prevents rotation but allows axial movement. The clutch housing 194 can be tightly affixed to the crankshaft 151 by means of splines 166, 167. The double clutch 150 is actuated in a familiar matter via the actuation devices 196, 197 that interact with actuating levers 198, 199.
On the drive-side end of the transmission shaft 152, there is a bearing journal 201 that is received by a blind hole 204 in the transmission-side end of the crankshaft 151. A needle bearing 206 also termed a pilot bearing is in the blind hole 204.
In the exemplary embodiment in
On the transmission side, the bearing inner race 225 is axially fixed to a step 228 on the transmission shaft 153. On the drive side, the bearing inner ring 225 is fixed by a snap ring 229 that is also termed a locking ring and engages in a ring groove in the drive shaft 153. A retention ring 231 is radially affixed to the outside of the bearing inner race 225 by a screw 230; the retention ring holds the locking ring 229 in the ring groove in the transmission shaft 153.
The hollow transmission shaft 153 is preferably mounted directly in a transmission housing (not shown). It can therefore enhance axial clutch support to affix the double clutch on the hollow shaft 153. This reduces axial play.
In the exemplary embodiment shown in
In addition, the hub 175 in the exemplary embodiment in
The circular cylinder jacket section of the hub bearing 235 is also termed an attachment section 239. The attachment section 239 of the hub bearing 235 is connected radially on the outside of the hub 175 of the first clutch disc 174. The hub bearing 235 is affixed to the drive-side end of the solid transmission shaft 152 with a screw 241. The attachment section 239 of the hub bearing 235 has a step 242 on its transmission-side end. The step 242 axially fixes a bearing device 243 for the intermediate pressure plate 170 on the solid transmission shaft 152. The bearing device 243 comprises a bearing outer race 244 that is affixed to the intermediate pressure plate 170 radially to the inside. In addition, the bearing device 243 comprises a bearing inner race that is radially mounted on the outside of the transmission-side end of the hub bearing 235. The bearing inner race 245 axially abuts the step 242. Rolling bodies 245 are between the bearing inner race 244 and the bearing outer race 246.
The bearing device 243 can be pre-mounted and hence axially fixed on the hub bearing 235. While mounting the double clutch 150 in a bell housing 247, the hub bearing 235 is shoved onto the drive-side end of the solid transmission shaft 152. The screw 241 for axially fixing the hub bearing 235 to the solid transmission shaft 152 can be easily reached during assembly. The axial support for the coupling force is provided via the step 242 on the hub bearing 235.
The tight connection between hub 175 and hub bearing 235 also enables the transmission of torque between the clutch disc 174 and the solid transmission shaft 152. It is particularly advantageous that the two clutch discs 174, 179 can have the same hub geometry due to the outer diameter of the attachment section 239.
In the exemplary embodiment shown in
In the exemplary embodiment shown in
In
The clutch housing part 168 has a flanged area 281 on the transmission side that has several feet 282, 283, 284. There are several through-holes 286, 287, 288 in the feet for fasteners. The clutch housing part 168 has a reinforcing edge 290 radially on the inside. The reinforcing edge 290 serves to minimize undesired deformation of the external spline 167.
FIGS. 14 to 16 show plan views of different exemplary embodiments of the damper output part 160. In all exemplary embodiments, two arms or fingers 161, 162 are diametrically opposed on the outside of the damper output part 160. In addition, the damper output part 160 is relatively thin in all three exemplary embodiments. When force is introduced through the bow springs of the dual-mass flywheel, there exists a tendency to bulge in a radial direction. By holding the damper output part 160 on the more rigid coupling housing part 168 (see
In the exemplary embodiment shown in
In the exemplary embodiment in
On the transmission side, friction linings 326 of a second clutch disc 327 can be held between the intermediate pressure plate 316 and the pressure plate 325. The second clutch disc 327 is coupled to a hub 329 by another vibration damper 328, and the hub is tightly mounted to the drive-side end of a hollow transmission shaft 153.
The transmission-side end of the hub bearing 322 has a peripheral step 330 against which axially abuts a bearing device 333 for the intermediate pressure plate 316. The bearing device 333 comprises a bearing outer race 334 that is affixed to the intermediate pressure plate 316 radially to the inside. In addition, the bearing device 133 comprises a bearing inner race 135 that is radially mounted on the hub bearing 322. Rolling bodies 336 are between the bearing inner race 335 and the bearing outer race 334.
In the exemplary embodiment in
In the exemplary embodiments shown in FIGS. 6 to 16, the actuating force of the double clutch is supported by the bearing device on one of the transmission input shafts. At the same time, the bearing device advantageously provides radial clutch support. The clutch can be pre-mounted in the bell housing. The two-mass flywheel can be pre-mounted on the crankshaft. The connection to the clutch is made in during assembly with spline toothing. The spline toothing axially decouples the clutch from the crankshaft vibration. The required radial compensation of the clutch in relation to the crankshaft is provided by the mobility of the damper output part in the two-mass flywheel. The damper output part with the internal spline is centered by the clutch housing part with the external spline, and it can be aligned at its contact sites with the parts of the two-mass flywheel.
Number | Date | Country | Kind |
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10 2004 042 640.6 | Sep 2004 | DE | national |
10 2004 051 476.3 | Oct 2004 | DE | national |