DE102021200719B4 - Powershift transmission group for a vehicle - Google Patents

Abstract

A power-shiftable transmission group (4) for a vehicle is proposed, with three shafts (1, 2, 3) with several spur gears (Z 80 to Z 87), with a first shaft (1) as an input shaft and a second shaft (2) as an output shaft and a third shaft (3) as a countershaft are arranged axially parallel to one another, with four multi-plate clutches (K1, K2, K3, KR) as switching elements for realizing three power-shiftable gear ratios (L, M, H) in the forward direction and one gear ratio (R ) are provided in the reverse direction, with only one switching element being switched to implement a gear ratio (L, M, H, ), and with a first disk carrier of each disk clutch (K1, K2, K3, KR) being connected to the associated shaft (1, 2, 3) is firmly connected and a second disk carrier of each disk clutch (K1, K2, K3, KR) is firmly connected to a spur gear (Z 80 to Z 87) which is rotatably mounted on one of the shafts (1, 2, 3). An agricultural utility vehicle with the transmission group (4) is also proposed.

Description

The present invention relates to a multi-gear, power-shiftable transmission group for a vehicle with three shafts with several spur gears and with four multi-plate clutches for realizing four gear ratios according to the type defined in more detail in the preamble of patent claim 1.

In vehicles, such as agricultural vehicles, transmission arrangements with a main transmission and an upstream transmission group are used, which are also referred to as splitters. This transmission group includes three shafts, each of which is assigned two clutches. In order to shift the gear ratios, it is necessary for two clutches to be closed in each case. Due to the large number of components required, such transmission groups are cost-intensive and require a large amount of space.

A transmission with a main shaft, three countershafts and a planetary gear is known from US 2005/0 101 426 A1. A planet carrier of the planetary gear is connected to a first countershaft, a sun gear of the planet carrier is connected to a second countershaft, and a ring gear of the planetary gear is connected to a third countershaft. Furthermore, the transmission includes four clutches, which can couple three different gear trains and a reverse gear train to the main shaft or separate them from the main shaft. A fifth clutch can couple or separate the planet carrier and the sun gear with each other.

the U.S. 5,971,883A describes a planetary gear set and four transfer gear pairs by means of which five forward gear ratios and two reverse gear ratios are provided in an automotive transmission. Three clutches controlling three of the gear pairs can be actuated in combination with two more clutches controlling the planetary gear set to provide four of the forward speeds and the two reverse speeds. Another clutch, which controls the fourth gear pair, represents another forward gear.

The present invention is based on the object of proposing a transmission group and an agricultural utility vehicle with the transmission group which are inexpensive and require less installation space.

This object is achieved according to the invention by the features of claims 1 and 11, respectively. Advantageous and claimed developments result from the dependent claims and the description as well as the drawings.

Thus, a multi-gear, power-shiftable transmission group for a vehicle with three shafts with several spur gears is proposed, with a first shaft as the input shaft of the transmission group and a second shaft as the output shaft of the transmission group and a third shaft as a countershaft being arranged axially parallel to one another. Furthermore, four multi-plate clutches are provided as switching elements for realizing three transmission stages in the forward direction and one transmission stage in the reverse direction. In order to design a particularly tree-friendly and cost-effective transmission group, it is provided that only one shifting element is switched to realize one or each transmission step and that a first disk carrier, i.e. an inner or outer disk carrier of each disk clutch, is firmly connected to the associated shaft and a second Disk carrier of each disk clutch is firmly connected to a spur gear rotatably mounted on one of the shafts.

With the proposed transmission group, a 3-way powershift group part is realized with as few components as possible. The 3-way splitter implements three power-shiftable gears for the forward direction and one power-shiftable gear for the reverse direction. Only four shifting elements or disk clutches and three shafts are required for this, with parts of the clutches or the inner or outer disk carrier being fixed directly to the shafts, for example by welding, riveting or the like. Due to the arrangement of the components in the proposed transmission group, the spur gears or the respective gear chains can each be arranged in a space-saving manner. Furthermore, multiple uses of spur gears for the transmission stage are possible.

The three waves used are arranged spatially parallel in the sense of an equivalent triangle. Each shaft assembly has multiple spur gears that are connected to the shaft as a fixed gear or to one of the clutches as an idler gear. In order to be able to shift a gear ratio, only one clutch needs to be closed and the other three clutches open.

In the proposed transmission group, the first shaft and the third shaft each have three spur gears, with two spur gears being designed as idler gears and one spur gear as a fixed gear. Furthermore, two multi-disc switching elements are assigned to the first shaft and the third. In contrast, only two spur gears, which are designed as fixed gears, are assigned to the second shaft. Consequently, the transmission group includes only eight gears or spur gears.

In the transmission group, the pitch circles of the spur gears are dimensioned and the shafts are arranged spatially relative to one another in such a way that the transmission group can be shown schematically in one plane without the third spur gears of the first and third shaft touching. Because of this advantageous arrangement in the proposed transmission group, these third spur gears of the first and third shaft can have identical teeth and can therefore be designed identically in terms of their number of teeth and their pitch circles. This results in a clear manufacturing advantage, which further reduces the manufacturing costs.

Furthermore, in the proposed transmission group, the first spur gear of the first shaft, which meshes with both the first spur gear of the third shaft and the first spur gear of the second shaft, has a higher number of teeth than the two aforementioned spur gears. This results in the advantageous arrangement already described on one level in a schematic representation of the transmission group.

In addition, it is provided in the claimed transmission group that the first spur gear of the third shaft and the first spur gear of the second shaft have the same number of teeth.

Another special feature of the proposed gear group is achieved in that the number of teeth of each spur gear of the gear group is a prime number. This results in particularly low-noise and low-resonance operation.

The proposed transmission group can preferably be used as a primary transmission group. This means that the first shaft of the transmission group is connected as an input shaft to a drive engine of the vehicle or utility vehicle and that the second shaft of the transmission group is connected as an output shaft to a main transmission of the vehicle. It is also conceivable that the proposed transmission group is used in a different way, for example as a rear-mounted group or the like in a vehicle.

A further aspect of the present invention lies in claiming an agricultural utility vehicle with the transmission group described above. This results in the advantages already described and other advantages.

The invention is explained in more detail below with reference to the drawings.

• 1 eine schematische Darstellung einer möglichen Ausführungsvariante einer erfindungsgemäßen Getriebegruppe für ein Fahrzeug;
• 2 eine schematische Darstellung der erfindungsgemäßen Getriebegruppe zum Realisieren einer kleineren Übersetzungsstufe in Vorwärtsfahrtrichtung;
• 3 eine schematische Darstellung der erfindungsgemäßen Getriebegruppe zum Realisieren einer mittleren Übersetzungsstufe in Vorwärtsfahrtrichtung;
• 4 eine schematische Darstellung der erfindungsgemäßen Getriebegruppe zum Realisieren einer höheren Übersetzungsstufe in Vorwärtsfahrtrichtung;
• 5 eine schematische Darstellung der erfindungsgemäßen Getriebegruppe zum Realisieren einer Übersetzungsstufe in Rückwärtsfahrtrichtung;
• 6 eine tabellarische Darstellung der Zähnezahlen der Stirnräder und der Übersetzungen der einzelnen Übersetzungsstufe der erfindungsgemäßen Getriebegruppe;
• 7 eine schematische Darstellung eines ersten Ausführungsbeispiels eines Antriebsstrang eines Nutzfahrzeuges mit der erfindungsgemäßen Getriebegruppe; und
• 8 eine schematische Darstellung eines zweiten Ausführungsbeispiels eines Antriebsstrang eines Nutzfahrzeuges mit der erfindungsgemäßen Getriebegruppe.

Show it:

• 1 a schematic representation of a possible embodiment of a transmission group according to the invention for a vehicle;
• 2 a schematic representation of the transmission group according to the invention for realizing a smaller gear ratio in the forward direction;
• 3 a schematic representation of the transmission group according to the invention for realizing a middle translation stage in the forward direction;
• 4 a schematic representation of the transmission group according to the invention for realizing a higher gear ratio in the forward direction;
• 5 a schematic representation of the transmission group according to the invention for realizing a gear ratio in the reverse direction;
• 6 a tabular representation of the number of teeth of the spur gears and the translations of the individual translation stage of the transmission group according to the invention;
• 7 a schematic representation of a first embodiment of a drive train of a commercial vehicle with the transmission group according to the invention; and
• 8th a schematic representation of a second embodiment of a drive train of a commercial vehicle with the transmission group according to the invention.

The figures show schematic representations of a transmission group according to the invention with indicated torque flows for the various gear ratio stages L, M, H, R that are engaged. Furthermore, exemplary embodiments of an agricultural utility vehicle with the transmission group according to the invention are only shown as examples.

For example off 1 it becomes clear that the multi-gear, power-shiftable transmission group 4 has three shafts 1, 2, 3 with several spur gears Z 80 to Z 87, with a first shaft 1 as the input shaft of transmission group 4 and a second shaft 2 as the output shaft of transmission group 4, as well as a third shaft 3 are arranged axially parallel to one another as a countershaft. Accordingly, the input shaft and the output shaft of the transmission group 4 are arranged axially offset from one another. Furthermore, four multi-plate clutches K1, K2, K3, KR are provided as switching elements for realizing three power-shiftable gear ratios L, M, H in the forward direction and one gear ratio R in the reverse direction.

In order to provide a particularly cost-effective and space-saving transmission group 4, only one shifting element is shifted or engaged when shifting each gear ratio L, M, H. Furthermore, a first disk carrier of each disk clutch K1, K2, K3, KR is firmly connected to the associated shaft 1, 2, 3 and a second disk carrier of each disk clutch K1, K2, K3, KR is rotatably connected to one of the shafts 1, 2, 3 mounted spur gear Z 80 to Z 87 firmly connected.

In the embodiment of transmission group 4 shown as an example, the outer disk carrier is firmly connected to the assigned shaft 1, 3 as a sort of first disk carrier for all multi-plate clutches K1, K2, K3, KR, and the inner disk carrier is essentially a second disk carrier with the assigned spur gear Z 80, Z 82, Z 83, Z 8. However, other versions are also conceivable.

As can be seen in particular from the 1 until 5 results, the transmission group 4 is designed as an upstream transmission group, since the first shaft 1 is connected as a transmission group input shaft to a drive motor An of the vehicle and the second shaft 2 is connected as a transmission group output shaft to a main transmission 5 shown as an example in the figures .

Furthermore, the first shaft 1 is assigned a first spur gear Z 83 as an idler gear, a second spur gear Z 84 as a fixed gear and a third spur gear Z 85 as an idler gear, as well as a first multi-plate clutch K1 and a second multi-plate clutch K2. Only a first spur gear Z 86 as a fixed gear and a second spur gear Z 87 as a fixed gear are assigned to the second shaft 2, while the third shaft 3 has a first spur gear Z 80 as an idler gear, a second spur gear Z 81 as a fixed gear and a third spur gear Z 82 are assigned as a loose wheel and a third multi-plate clutch K3 and a fourth multi-plate clutch KR.

The pitch circles of the spur gears Z 80 to Z87 are dimensioned in such a way and the shafts 1, 2, 3 are arranged spatially in relation to one another in such a way that the first spur gear Z 83 of the first shaft 1 can be connected both to the first spur gear Z 86 of the second shaft 2 and to the first Spur gear Z 80 of the third shaft 3 meshes, that the second spur gear Z 84 of the first shaft 1 meshes with the second spur gear Z 81 of the third shaft 3, and that the third spur gear Z 85 of the first shaft 1 meshes with the second gear Z 87 of the second shaft 2 is in engagement, the second spur gear Z 87 of the second shaft 2 being in engagement with the third spur gear Z 82 of the third shaft 3, which is indicated by a dot-dash line.

Furthermore, it is provided that the third spur gear Z 85 of the first shaft 1 and the third spur gear Z 82 of the third shaft 3 are identical in terms of their number of teeth and their pitch circles. In addition, the first spur gear Z 83 of the first shaft 1 has a higher number of teeth than the first spur gear Z 80 of the third shaft 3 and the first spur gear Z 86 of the second shaft 2 . In addition, the first spur gear Z 80 of the third shaft 3 and the first spur gear Z 86 of the second shaft 2 have the same number of teeth. Finally, in the gear group 4, in order to reduce the running noise and the resonance, the number of teeth of each spur gear Z 80 to Z 87 is a prime number.

In 2 the torque flow is indicated with a switched small or smaller gear ratio L in the forward direction in transmission group 4. In order to implement the lower gear ratio L in the forward direction of travel, the first shaft 1 as the input shaft is connected to the second spur gear Z 85 of the first shaft 1 via the closed first multi-plate clutch K1, with the second spur gear Z 85 being connected to the second spur gear Z 87 as the fixed gear of the second shaft 2 is engaged as an output shaft. The Low L transmission stage is thus shifted by means of the first multi-plate clutch K1. This has the advantage that the gear or the spur gear Z 87 needs a higher number of teeth than the spur gears Z 82 and Z 85 for the gear reduction. Due to the resulting pitch circles, the arrangement on one level is possible without the spur gears Touch Z 85 and Z 82. As a result, the spur gears Z 85 and Z 82 can be designed identically.

In 3 the torque flow is indicated with a switched middle transmission stage M in the forward direction in transmission group 4. To achieve the middle transmission stage M in the forward direction of travel, the first shaft 1 as the input shaft is connected to the first spur gear Z 83 of the first shaft 1 via the closed second multi-plate clutch K2, with the first spur gear Z 83 being connected to the first spur gear Z 86 as the fixed gear of the second shaft 2 is engaged as an output shaft. As a result, the middle transmission step Middle M is shifted with the second multi-plate clutch K2. With a ratio of i less than 0.98, arrangement on one level is still possible. In the present example, the gear ratio was set as close as possible to i equal to 1 (here i_M equal to 0.967). As a result, an advantageously balanced relationship between speed and torque is achieved. The first spur gear Z 83 has a higher number of teeth than the spur gears Z 80 and Z 86. This makes it possible to arrange them on one level. The spur gears Z 80 and Z 86 can have the same toothing.

In 4 is the torque flow with a switched high or higher translation Stage H indicated in the forward direction of transmission group 4. To achieve a higher gear ratio H in the forward direction of travel, the first shaft 1 is connected as an input shaft via the second spur gear Z 84 of the first shaft 1 and the second spur gear Z 81 of the third shaft 3 and via the closed third multi-plate clutch K3 to the first spur gear Z 80 of the third Shaft 3 is connected, the first spur gear Z 80 being connected via the first spur gear Z 83 of the first shaft 1 to the first spur gear Z 86 as a fixed gear of the second shaft 2 as the output shaft. The high or higher transmission stage High H is thus switched via the third multi-plate clutch K3. A gear jump of approx. 25% is realized between the gear ratio stages LMH in the gearing example shown. This spread represents a suitable compromise between the load on the clutch and the speed that can be achieved.

In 5 the torque flow is indicated with a shifted gear ratio R in the reverse direction in transmission group 4. To implement the gear ratio R in the reverse direction, the first shaft 1 is connected as an input shaft via the second spur gear Z 84 of the first shaft 1 and the second spur gear Z 81 of the third shaft 3 and via the closed fourth multi-plate clutch KR with the third spur gear Z 82 of the third shaft 3 connected, with the third spur gear Z 82 meshing with the second spur gear Z 87 of the second shaft 2 as the output shaft. Thus, the Reverse R transmission stage is shifted with the fourth multi-plate clutch KR. The reversal of the direction of rotation on the second shaft 2 or output shaft is realized by the toothing engagement between the spur gears Z 82 and Z 87 . Due to the gearing combination selected, a transmission similar to that of the medium transmission stage M is achieved. This has the advantage that it is possible to reverse to reverse gear and vice versa in each power shift stage in the forward direction.

6 shows the number of teeth of the spur gears Z 80 to Z 87 in tabular form. The gear ratios L, M, H, R assigned to the spur gears Z 80 to Z 87 are also given. In addition, in 6 the translations i assigned to the translation stages as well as the spread are given as an example for the translation stages L and M.

In the 7 and 8th only exemplary embodiments or application examples of the transmission group 4 according to the invention are shown in a tractor or an agricultural utility vehicle with a main transmission 5 connected downstream.

7 shows the first exemplary embodiment, in which the drive train of the utility vehicle has 18 gears in the forward direction and 6 gears in the reverse direction. The first shaft 1 of the transmission group 4 can be connected to the drive motor An and to a power take-off 6 . The second shaft 2 of the transmission group 4 is connected to an input of the main transmission 5 . The main transmission 5 can drive both a front axle and a rear axle of the utility vehicle.

8th shows the second embodiment, in which the drive train of the utility vehicle has 15 gears in the forward direction and 5 gears in the reverse direction. In this application example, too, the input shaft of the transmission group 4 can be connected to an auxiliary drive 6 and the output shaft of the transmission group 4 can be connected to the input of a main transmission 5, with which both the front axle and the rear axle can be driven.

Reference List

1

first shaft or input shaft of the transmission group

2

second shaft or output shaft of the transmission group

3

third shaft or countershaft

4

gear group

5

main gear

6

PTO

L

lower or smaller translation level

M

middle or medium translation level

H

high or higher translation level

R

reverse or gear ratio reverse direction

i

translation

K1

first multi-plate clutch

K2

second multi-plate clutch

K3

third multi-plate clutch

KR

fourth multi-plate clutch

Z 80

first spur gear as idler gear of the third shaft

Z 81

second spur gear as a fixed gear of the third shaft

Z 82

third spur gear as idler gear of the third shaft

Z 83

first spur gear as idler gear of the first shaft

Z 84

second spur gear as a fixed gear of the first shaft

Z 85

third spur gear as idler gear of the first shaft

Z 86

first spur gear as a fixed gear of the second shaft

Z 87

second spur gear as a fixed gear of the second shaft

On

drive motor

Claims (11)

Power-shiftable transmission group (4) for a vehicle, with three shafts (1, 2, 3) with several spur gears (Z 80 to Z 87), with a first shaft (1) as an input shaft and a second shaft (2) as an output shaft and a third shaft (3) as a countershaft are arranged axis-parallel to each other, and with four multi-plate clutches (K1, K2, K3, KR) as switching elements for realizing three power-shiftable gear ratios (L, M, H) in the forward direction and one gear ratio (R) in the reverse direction , wherein only one shifting element is shifted to realize a gear ratio (L, M, H, ), and wherein a first disk carrier of each disk clutch (K1, K2, K3, KR) is permanently connected to the assigned shaft (1, 2, 3). and a second disk carrier of each disk clutch (K1, K2, K3, KR) is firmly connected to a spur gear (Z 80 to Z 87) rotatably mounted on one of the shafts (1, 2, 3), characterized in that the first shaft ( 1) a first spur gear (Z 83) as an idler gear, a second spur gear (Z 84) as a fixed gear and a third spur gear (Z 85) as an idler gear as well as a first multi-plate clutch (K1) and a second multi-plate clutch (K2) that the second shaft (2) has a first spur gear ( Z 86) as a fixed gear and a second spur gear (Z 87) as a fixed gear, and that the third shaft (3) has a first spur gear (Z 80) as an idler gear, a second spur gear (Z 81) as a fixed gear and a third spur gear ( Z 82) as a loose wheel and a third multi-plate clutch (K3) and a fourth multi-plate clutch (KR) are assigned and that the pitch circles of the spur gears are dimensioned and the shafts (1, 2, 3) are spatially arranged in relation to one another in such a way that the first spur gear ( Z 83) of the first shaft (1) meshes both with the first spur gear (Z 86) of the second shaft (2) and with the first spur gear (Z 80) of the third shaft (3), so that the second spur gear (Z 84) of the first shaft (1) meshes with the second spur gear (Z 81) of the third shaft (3). and that the third spur gear (Z 85) of the first shaft (1) meshes with the second spur gear (Z 87) of the second shaft (2), the second spur gear (Z 87) of the second shaft (2) with the third spur gear (Z 82) of the third shaft (3) is engaged. Transmission group (4) after claim 1 , characterized in that the third spur gear (Z 85) of the first shaft (1) and the third spur gear (Z 82) of the third shaft (3) are identical in terms of their number of teeth and/or their pitch circles. Transmission group (4) according to one of the preceding claims, characterized in that the first spur gear (Z 83) of the first shaft (1) has a higher number of teeth than the first spur gear (Z 80) of the third shaft (3) and the first spur gear (Z 86) of the second shaft (2). Transmission group (4) according to one of the preceding claims, characterized in that the first spur gear (Z 80) of the third shaft (3) and the first spur gear (Z 86) of the second shaft (2) have the same number of teeth. Transmission group (4) according to one of the preceding claims, characterized in that the number of teeth of each spur gear (Z 80 to Z 87) is a prime number. Transmission group (4) according to one of the preceding claims, characterized in that in order to implement a smaller gear ratio (L) in the forward direction of travel, the first shaft (1) as the transmission group input shaft is connected to the second spur gear (Z 85) via the closed first multi-plate clutch (K1) connected to the first shaft (1), which meshes with the second spur gear (Z 87) as a fixed gear of the second shaft (2) as the transmission group output shaft. Transmission group (4) according to one of the preceding claims, characterized in that in order to realize a medium gear ratio (M) in the forward direction of travel, the first shaft (1) as the transmission group input shaft is connected to the first spur gear (Z 83) via the closed second multi-plate clutch (K2) is connected to the first shaft (1), which meshes with the first spur gear (Z 86) as a fixed gear of the second shaft (2) as a transmission group output shaft. Transmission group (4) according to one of the preceding claims, characterized in that in order to implement a higher gear ratio (H) in the forward direction of travel, the first shaft (1) as the transmission group input shaft via the second spur gear (Z 84) of the first shaft (1) and the second spur gear (Z 81) of the third shaft (3) and via the closed third multi-plate clutch (K3) to the first spur gear (Z 80) of the third shaft (3), which via the first spur gear (Z 83) of the first shaft (1) is connected to the first spur gear (Z 86) as a fixed gear of the second shaft (2) as a transmission group output shaft. Transmission group (4) according to one of the preceding claims, characterized in that in order to implement a gear ratio (R) in the reverse direction, the first shaft (1) as a transmission group input shaft via the second spur gear (Z 84) of the first shaft (1) and the second Spur gear (Z 81) of the third shaft (3) and via the closed fourth multi-plate clutch (KR) to the third spur gear (Z 82) of the third shaft (3), which is connected to the second spur gear (Z 87) of the second shaft ( 2) engages as a transmission section output shaft. Gear group (4) according to one of the preceding claims, characterized in that it is designed as a front-mounted gear group, the first shaft (1) being connected as a gear group input shaft to a drive motor (An) of the vehicle and the second shaft (2 ) is connected as a transmission group output shaft to an input of a main transmission (5). Agricultural utility vehicle with a transmission group (4) according to one of the preceding claims.

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