Isolating the transmission tunnel of a motor vehicle

Abstract

A transmission tunnel (10) for a motor vehicle, comprising an elongated tunnel cavity (12) formed by a floor plate (14) and at least partially enclosed by tunnel walls (16) of the floor plate (14), which forms a first receiving area (18) at the front in the direction of travel (F) for receiving a part of a transmission assembly (38) and a second receiving area (20) at the rear in the direction of travel for guiding a drive train; and a tunnel partition (24); wherein a first spacer area (26) is provided in the first receiving area (18) along the tunnel wall (16), which forms a first free area when the transmission assembly (38) is received; wherein the tunnel partition (24) is arranged in the tunnel cavity (12) and separates the first spacer area (26) from the second receiving area (20), wherein a transmission support (28) is provided for supporting a rear end of a transmission assembly (38) in the direction of travel;and wherein the tunnel bulkhead (24) is arranged in the area of ​​the gearbox mount (28).

Description

The present invention relates to a partitioning in a transmission tunnel, and relates in particular to a transmission tunnel for a motor vehicle, a floor group for a motor vehicle, a motor vehicle, and the use of a transmission tunnel in a passenger motor vehicle.Vehicles with rear drive or also with all-wheel drive are designed, for example, with a continuous tunnel in the region of the vehicle floor in order to guide the output shaft for the rear wheels from the front engine region to the rear. The transmission tunnel can also be used to guide an exhaust line to the rear in this region, or else below it. In the rear region of the vehicle, for example, a tank can be provided below the floor panel, for example in the region below the rear seat bank.In order to protect the fuel tank from too high a heat supply, heat shielding plates are provided, for example, above the exhaust gas duct in order to shield the exhaust gas duct from the fuel tank. From U.S. Pat. No. 5,813,491 A, for example, an underbody structure is known in which warm air from the engine compartment, and also warm air that heats up along the exhaust gas duct, is mixed with cooler air and is guided along the exhaust gas line via an air duct above the fuel tank in order to cool the exhaust gas line, so that the heat input to the fuel tank is reduced. DE 10 2008 036 179 A1 discloses a floor structure for a motor vehicle.However, it has been found that, particularly in connection with large-volume engines, the fuel tank, and also other components, are exposed to large thermal loads of the heat produced by the engine and exhaust system.For example, there is a need for improved fuel tank thermal protection.This object is achieved by a transmission tunnel, a floor group and a vehicle, and a use of a transmission tunnel according to one of the independent claims. Exemplary embodiments are set forth in the dependent claims.According to the invention, a transmission tunnel for a motor vehicle is provided, which has an elongate tunnel cavity formed by a floor panel and at least partially surrounded by tunnel walls of the floor panel, which tunnel cavity forms a first receiving region at the front in the direction of travel for receiving a part of a transmission assembly and a second receiving region at the rear in the direction of travel for guiding an output train.In addition, the transmission tunnel has a tunnel partition. In the first receiving region, a first spacing region is provided along the tunnel wall, which forms a first free region when the transmission assembly is received. The tunnel partition is arranged in the tunnel cavity and separates the first spacing region from the second receiving region.By disposing the tunnel partition at the end of the area in which a transmission can be accommodated, hot air flowing from the area of the engine compartment into the transmission tunnel is prevented from flowing further along the transmission tunnel toward the fuel tank. By partitioning the transmission tunnel, a thermal protection measure of the fuel tank is thus already provided in the front area, namely in a front or maximum middle region of the transmission tunnel.The terms "rear" or "front" refer to the main directions of travel of the vehicle. The tunnel cavity extends in the longitudinal direction of the vehicle, e.g. along the longitudinal central axis of the vehicle. The term "separating" the first spacing region from the second receiving region refers to the interruption, or at least a substantial reduction, of the air flow from the first spacing region to the second receiving region.In the invention, a transmission holder is provided for supporting an end of a transmission assembly that is at the rear in the direction of travel, wherein the tunnel partition is arranged in the region of the transmission holder.For example, the first receiving region extends from a front end of the tunnel cavity at least as far as the transmission holder.According to one example, the tunnel partition is designed as at least one partition fastened on one side to the tunnel wall and having a flexible connection region for abutting connection to the transmission assembly.According to a further example, the tunnel partition is designed as at least one partition fastened on one side to the transmission unit with a flexible connection region for abutting connection to the tunnel wall.In a further example, the two variants mentioned are provided together.The flexible connection region is designed, for example, as a brush seal. The flexible connection region can also be designed as a flexible seal, for example made of rubber or fabric, with adjustability to variable distances of the gap between the partition and the adjoining surface.In another example, the tunnel partition is formed fastened on both sides to the tunnel wall and the transmission assembly. In a further example, the tunnel partition is designed as a two-part cuff (double cuff).For example, the tunnel wall is formed with sound insulation, and the tunnel partition is held on fastening elements of the sound insulation. Sound insulation is also referred to as sound insulation.In a further example, the tunnel partition has a plurality of partitions, for example a plurality of partitions fastened on one side to the tunnel wall and having flexible connection regions for abutting connection to the transmission assembly. In addition, or alternatively, the tunnel partition has a plurality of partitions fastened on one side to the transmission unit and having flexible connection regions for abutting connection to the tunnel wall.In one example, the tunnel partition has at least one multi-part partition. For example, a plate partition with several sealing plates is provided, which are arranged one behind the other in the flow direction.In one example, the tunnel partition is designed as complementary contour segments on the tunnel walls and on outer sides of the transmission assembly.For example, the tunnel wall is formed with sound insulation which is formed with a protruding profile segment, and the gear unit has a mating contour formed in the direction of the protruding profile segment.According to the invention, a floor group for a motor vehicle is also provided, which has a transmission device connectable to an engine, an output train for driving a rear axle, and a transmission tunnel according to one of the preceding examples. The transmission device has at least one transmission assembly which is at least partially accommodated in the tunnel cavity.The output train is connected to the transmission assembly and is at least partially accommodated in the tunnel cavity. Between the at least one gear unit and the adjacent tunnel wall, a free intermediate space is present, which forms the first free region. The first free region is bounded towards the rear by the tunnel partition.The term "limit" refers to a limitation of an airflow path from the first free area to a region behind it. For example, air flow during vehicle operation is reduced by at least half, e.g., at least two-thirds. For example, air flow is fully prohibited during vehicle operation.The tunnel partition is formed, for example, over almost the entire width of the gap or distance between the tunnel wall and the transmission assembly, for example over at least approximately 75%, or 80%, or 90%, or 95% of the gap or distance.The term "floor group" refers within the scope of the present invention to the floor panel that forms the transmission tunnel and the components of the drive that are arranged in the transmission tunnel as well as the tunnel partition. In contrast, the term "underbody" is also used in the vehicle industry to identify an assembly which, for example, refers to, inter alia, the floor panel with add-on parts, but which (still) does not have a transmission.Within the scope of the present invention, however, at least the component projecting into the transmission tunnel is provided in the "floor group". For the term "subassembly", however, other designations can also be used, such as, for example, subassembly with transmission device, subassembly device, subassembly device, or else subassembly collection of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of the subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of the subassemblies of subassemblies of subassemblies of subassemblies of subassemblies of the type.According to one example, the tunnel partition is arranged in the area of the transmission device.According to one example, the gear unit has a contour line which projects into the region of the tunnel cavity, and the tunnel partition is arranged behind the projecting contour line in the direction of travel.The transmission assembly is, for example, a transmission or a transmission with a transfer case. In one example, the output train is connected to the transmission unit via a front articulation disk, and the tunnel partition is arranged in front of the front articulation disk. The transmission is, for example, an automatic transmission. In another example, the transmission is a manual transmission. In a further example, the transfer case is also formed with a second output train for driving the front axle. The engine is, for example, an internal combustion engine. In one example, the engine is configured with an overhead exhaust guide, e.g., as a V8 engine with an overhead interface between the cylinder banks. The exhaust gas guide can be arranged, for example, in the intermediate region. In another example, the engine is an internal combustion engine having six, four, or three cylinders, e.g., in an in-line arrangement. In another example, the engine is a ten or twelve cylinder internal combustion engine, e.g., in a V-arrangement.According to another example, the first free region is open downward and forms an airflow opening for airflow from an engine compartment region to a region below the underbody. In addition, a heat protection cover is provided, which closes the second receiving region of the tunnels on a longitudinal side. The thermal protection cover connects to the transmission assembly at the front end in such a way that a separate cavity is formed, which is delimited at the front end by the tunnel partition and the transmission assembly from the first receiving region.The heat protection cover is designed, for example, as a heat protection sheet. The longitudinal side is, for example, a lower longitudinal side of a downwardly open U-shaped tunnel cavity.According to a further example, the tunnel walls are formed in the first free region on the side facing the tunnel cavity with air directing devices in order to discharge the air flow present during vehicle operation in the downward direction.For example, air guidance projections are provided which extend obliquely downwards from the front to the rear in order to reduce the air flowing into the tunnel partition. For example, the air guiding projections are formed in the base plate. In another example, the air guiding projections are formed on sound insulation or sound insulation.According to the invention, there is also provided a motor vehicle having a underbody according to any preceding example and an engine compartment region provided in the front part of the vehicle and having an internal combustion engine arranged therein and connected to the transmission device. The tunnel partition deflects an air flow occurring during vehicle operation from the engine compartment region in the direction of the region behind the tunnel partition in the downward direction.The motor vehicle is, for example, a passenger car.According to the invention, the use of a transmission tunnel according to one of the preceding examples is also provided in a passenger motor vehicle having an internal combustion engine.According to one aspect of the invention, a partitioning means is provided in a transmission tunnel at a central location at which the transmission is held on a transmission mounting. The partitioning prevents an air flow with hot air from the region of the engine compartment from reaching the rear region of the transmission tunnel, and in particular from reaching the fuel tank.By means of the partitioning, for example, a connection of the transmission output line to the transmission, for example a joint disk, is also partitioned off, so that a lower heat supply takes place in this region as well, which additionally protects heat-sensitive components present there, such as the front joint disk, for example.By arranging the partitioning in the course of the transmission tunnel, an air discharge from the region of the engine compartment is additionally provided at least over a part of the transmission tunnel in the downward direction. Overall, the dissipation of heat is ensured by an air flow which is produced during vehicle operation and which can also be supported or generated by a fan additionally or also when the vehicle is at a standstill.It should be noted that the features of the exemplary embodiments of the transmission tunnel also apply to embodiments of the underbody and of the motor vehicle and also to the use, and vice versa. In addition, those features in which this is not explicitly mentioned can also be freely combined with one another, wherein synergistic effects can result which go beyond the addition of the aspects of the various features.Exemplary embodiments of the invention are discussed in more detail below with reference to the appended drawings. The following are shown: FIG. 1 shows an example of a transmission tunnel in a schematic longitudinal section; FIG. 2 shows an example of a base group in a longitudinal section; FIG. 3 shows a further example of a base group in a longitudinal section; and FIG. 4A shows a floor group in cross section in a first example, in which a tunnel partition is fastened on one side to the tunnel wall; FIG. 4B shows a floor group in cross section in a second example, in which the tunnel partition is fastened on one side to the transmission unit; FIG. 4C shows a floor group in cross section in a third example, in which the partitioning means is fastened to the transmission unit and to the tunnel wall.FIG. 1 shows a transmission tunnel 10 for a motor vehicle in a longitudinal section. The transmission tunnel 10 has a tunnel cavity 12 which is formed by a floor panel 14. As can be seen in FIGS. 4A, 4B and 4C, the elongate tunnel cavity 12 is at least partially surrounded by tunnel walls 16 of the floor panel 14. The elongated tunnel cavity 12 defines a front first receiving region 18 and a rear second receiving region 20.In FIG. 1, the direction of travel F is indicated by a direction of travel arrow 22. In other words, the vehicle front is on the left in FIG. 1 and the vehicle rear is on the right. The first receiving region 18 is provided to receive a part of a transmission assembly, which is indicated by a dashed representation of the transmission assembly. The second receiving region 20 is designed for guiding an output drive train, which is likewise indicated. In addition, a tunnel partition 24 is provided, which will be explained in more detail below.In the first receiving region 18, a first spacer region 26 is provided along the tunnel wall 16, which forms a first free region when the transmission assembly is received. The tunnel partition 24 is arranged in the tunnel cavity 12 and separates the first spacing region 26 from the second receiving region 20.For example, a transmission holder 28 for supporting a rear end of a transmission assembly in the direction of travel may be provided. The tunnel partition 24 is arranged, for example, in the region of the transmission holder 28. The term "in the region" refers to an arrangement, for example, in the immediate vicinity of the transmission holder 28, for example, at a distance of up to a maximum of 10 cm, or for example, 5 cm or even directly above the transmission holder 28.It is also indicated in FIG. 1 that the transmission tunnel can merge into an end wall 15 in a front region, i.e. in the left-hand region in FIG. 1, to which additional enclosing surfaces of the engine compartment, e.g. a front hood, can be connected, for example.The front wall is, however, not an obligatory component of the transmission tunnel. It is likewise indicated that the transmission tunnel 12 can have a recessed contour 17 at the rear end in order to form a receiving region for a fuel tank.In FIG. 1, the viewing edge of the tunnel wall is indicated by a thin dotted line 19, which is visible when the transmission tunnel 10 is shown cut in the longitudinal direction in the middle.FIG. 2 shows a longitudinal section of a floor assembly 30 for a motor vehicle. The base group 30 has a transmission device 32 which can be connected to an engine 34. However, the motor 34 does not represent a necessary component of the underbody, but merely serves to illustrate the option of connection to the transmission device 32.The underbody 30 also has an output train 36 for driving a rear axle, not shown in more detail. In addition, the floor group 30 has a transmission tunnel 10 according to one of the examples described above. The transmission device 32 has at least one transmission assembly 38 which is at least partially accommodated in the tunnel cavity 12.In FIG. 2, the transmission device includes an automatic transmission 40 and a transfer case 42. The output train 36 for the rear axle is connected to the transfer case 42 via a front articulated disk 44. On the transfer case 42, a second output train 46 is also provided for driving a front axle, for example for an all-wheel drive vehicle. As already mentioned, the output train 36 is connected to the transmission assembly 38 and is at least partially accommodated in the tunnel cavity 12.Between the at least one gear unit 38 and the adjacent tunnel wall, a free intermediate space 48 is present, which forms the first free region in the region of the first spacing region 26. The first free region is bounded towards the rear by the tunnel partition 24. In FIG. 2, an exhaust system 50 is also indicated, which is, however, only shown as an option for the underbody 30. For example, the exhaust system 50 connects to the engine block in the upper region, i.e. in a region above the engine 34, and guides the exhaust gases laterally past the transmission device into a region below the transmission device and the output drive.For example, the exhaust gas is guided into the rear region of the vehicle by one or more exhaust gas guide tubes 52 in order to be discharged there as exhaust gas to the environment, of course after passing through an exhaust gas purification system.As already mentioned, for example, the tunnel partition 24 is provided in the region of the transmission device 32, for example at the rear end.According to an example not shown in more detail, it is provided that the gear unit 38 has a contour line protruding into the region of the tunnel cavity 12, and the tunnel partition 24 is arranged behind the protruding contour line in the direction of travel.In another example, also shown optionally in FIG. 2, the first free portion of the first spacer portion 26 is open downwardly and defines an airflow opening for airflow, indicated by airflow arrows 54, from an engine compartment portion 56 to an under-floor portion 58.In addition, a heat protection cover 60 can be provided, which closes the second receiving region 20 of the tunnel on a longitudinal side, for example on the lower side. The thermal protection cover 60 can connect to the transmission assembly at the front end 62 in such a way that a separate cavity 64 is formed, which is delimited at the front end by the tunnel partition 24 and the transmission assembly 38 from the first receiving region 18.The thermal shield cover 60 is, for example, a thermal shield that is connected to the transmission bracket 28. In FIG. 2, a fuel tank device 61 is also indicated, which is provided above the output line 36 and also above the thermal protection cover 60.FIG. 3 shows a further exemplary embodiment in which the transmission device 32 has only one transmission 66, to which the output train 36 with the front articulated disk 44 is connected. The partition 24 can be arranged, for example, above the transmission holder 28, to which the thermal protection cover 60 is also connected. The partition 24 has a passage opening for the output line 36.The arrangement of the heat partition 24 in the region of the transmission holder offers the advantage that a simple connection to the heat protection cover 60 can be achieved by means of the transmission holder 28. Since in this case the front joint disk 44 is likewise exposed to the hot air flow, since the joint disk 44 is arranged in front of the partition 24, this can be adapted for this situation by further measures, for example more temperature-resistant material.As already mentioned, the partition 24 is arranged in the transmission tunnel in such a way that, in a front region, an air flow originating from the front of the engine compartment 56 can flow first of all to the rear in the transmission tunnel in order then to be deflected downward, for example with the aid of the partition 24 acting as a partition.In a further example, not shown, the tunnel walls are formed in the first free region on the side facing the tunnel cavity with air directing devices in order to divert the air flow present during vehicle operation downward. For example, air guidance projections are provided which extend obliquely downwards from the front to the rear in order to reduce the air flowing into the tunnel partition.As is schematically indicated in a cross section in FIG. 4A, it is provided that the tunnel partition in the example shown in FIG. 4A is formed as at least one partition 68 which is fastened on one side to the tunnel wall and which is formed with a flexible connection region 70 for abutting connection to the transmission assembly 38.FIG. 4B shows a further example in which the tunnel partition 24 is a partition 72 fastened on one side to the transmission assembly 38, having a flexible connection region 74 for abutting connection to the tunnel wall 16.FIG. 4C shows a further example in which the tunnel partition 24 is designed as a partition 76 fastened on both sides to the tunnel wall 16 and the transmission assembly 38.According to a further example, a motor vehicle is provided in which a underbody according to one of the preceding examples is provided, and an engine region provided in the front vehicle part, having an internal combustion engine arranged therein, which is connected to the transmission device of the underbody. The tunnel partition deflects an air flow occurring during vehicle operation from the engine compartment region in the direction of the region behind the tunnel partition in a downward direction.According to the invention, the partition 24 prevents warm air flowing out of the engine compartment from being forced into the tunnel and flowing along it to the rear. The components located behind the partition 24 are protected from the warm air, in particular the fuel tank, the bearings of the output line and, for example, also the joint disk. This achieves a temperature reduction of the components arranged in the tunnel and in the underbody region, in particular of the fuel tank.The above-described exemplary embodiments can be combined in different ways. In particular, aspects of the method can also be used for embodiments of the devices and use of the devices, and vice versa.Additionally, it should be noted that "comprising" does not exclude other elements or steps and "a" or "an" does not exclude a plurality. It should also be noted that features or steps that have been described with reference to one of the above exemplary embodiments and aspects can also be used in combination with other features or steps of other exemplary embodiments and aspects described above. Reference signs in the claims should not be regarded as limiting.

Claims

Transmission tunnel (10) for a motor vehicle, having an elongate tunnel cavity (12) which is formed by a floor panel (14) and is at least partially surrounded by tunnel walls (16) of the floor panel (14) and forms a first receiving region (18), which is at the front in the direction of travel (F), for receiving part of a transmission assembly (38) and a second receiving region (20), which is at the rear in the direction of travel, for guiding an output train; and a tunnel partition (24); wherein a first spacing region (26) is provided along the tunnel wall (16) in the first receiving region (18), said spacing region forming a first free region when the transmission assembly (38) is received; wherein the tunnel partition (24) is arranged in the tunnel cavity (12) and separates the first spacer region (26) from the second receiving region (20), wherein a transmission mounting (28) is provided for mounting an end of a transmission assembly (38) which is at the rear in the direction of travel; and wherein the tunnel partition (24) is arranged in the region of the transmission mounting (28).Transmission tunnel (10) according to Claim 1, wherein the tunnel partition (24) is designed as at least one partition (68), which is fastened on one side to the tunnel wall (16), having a flexible connection region (70) for abutting connection to the transmission assembly (38); and / or as at least one partition (72), which is fastened on one side to the transmission assembly (38), having a flexible connection region (74) for abutting connection to the tunnel wall (16).A floor assembly (30) for a motor vehicle, comprising a transmission device (32) connectable to an engine; an output train (36) for driving a rear axle; and a transmission tunnel (10) according to any one of the preceding claims; wherein the transmission device (32) comprises at least one transmission assembly (38) which is at least partially accommodated in the tunnel cavity (12); and wherein the output train is connected to the transmission assembly (38) and is at least partially accommodated in the tunnel cavity (12); and wherein between the at least one transmission assembly (38) and the adjacent tunnel wall (16) there is a free intermediate space (48) which forms the first free region; and wherein the first free region is bounded towards the rear by the tunnel partition (24).The underbody (30) according to claim 3, wherein the tunnel partition (24) is arranged in the region of the transmission device (32).The underbody (30) according to claim 3 or 4, wherein the gear unit (38) has a contour line protruding into the region of the tunnel cavity (12); and wherein the tunnel partition (24) is arranged behind the protruding contour line in the direction of travel.The underbody (30) according to claim 3, 4 or 5, wherein the first free region is open downward and forms an air flow opening for an air flow (54) from an engine compartment region (56) to a region (58) below the underbody; and wherein a thermal protection cover (60) is provided which closes the second receiving region (20) of the tunnel on a longitudinal side; and wherein the thermal protection cover (60) connects to the transmission assembly (38) at the front end (62) in such a way that a separate cavity (64) is formed which is delimited at the front end by the tunnel partition (24) and the transmission assembly (38) from the first receiving region (18).The underbody (30) according to claim 3, 4, 5 or 6, wherein the tunnel walls (16) are formed in the first free area on the side facing the tunnel cavity (12) with air deflectors for diverting the air flow present during vehicle operation downward.Motor vehicle, wherein: - the motor vehicle has a base group (30); - the base group (30) has: ◯ a transmission device (32); ◯ an output train (36) for driving a rear axle; and ◯ a transmission tunnel (10), which has: ▪ an elongate tunnel cavity (12), which is formed by a base plate (14) and is at least partially surrounded by tunnel walls (16) of the base plate (14) and has a first receiving region (18) at the front in the direction of travel (F) and a second receiving region (20) at the rear in the direction of travel (20); and ▪ a tunnel partition (24); - the transmission device (32) has at least one transmission assembly (38), which is at least partially received in the tunnel cavity (12); - a part of the transmission assembly (38) is received in the first receiving region (18); the output line is connected to the transmission assembly (38) and is at least partially accommodated in the tunnel cavity (12); the output line is guided in the second accommodation region (20); a first spacing region (26), which forms a first free region, is provided in the first accommodation region (18) along the tunnel wall (16); the tunnel partition (24) is arranged in the tunnel cavity (12) and separates the first spacing region (26) from the second accommodation region (20); a free intermediate space (48), which forms the first free region, is present between the at least one transmission assembly (38) and the adjacent tunnel wall (16); the first free region is bounded towards the rear by the tunnel partition (24); the motor vehicle has an engine compartment region (56) provided in the front vehicle part and having an internal combustion engine arranged therein, which is connected to the transmission device (32); and the tunnel partition (24) deflects an air flow occurring during vehicle operation from the engine compartment region (56) in the direction of the region behind the tunnel partition (24) downwards.Use of a transmission tunnel according to Claim 1 or 2 in a passenger vehicle having an internal combustion engine.

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