Combined multi-stage gearing

Abstract

A combined multistage gearing has a spur gearing having at least one first and one second spur wheel arranged on a spur gear shaft, an epicyclic gearing having at least one first and one second, in particular reduced, planetary wheel set and an epicyclic gearing shaft, wherein at least one of the planetary wheel sets is arranged concentrically to the epicyclic gearing shaft, a gearing housing, wherein the spur gear shaft and the epicyclic gearing shaft are rotatably mounted relative to the gearing housing, and a plurality of switching apparatuses. The first spur gear can be selectively connected in a torque-transmitting manner to the spur gear shaft. The first spur gear can be selectively connected in a torque-transmitting manner to the gearing housing.

Claims

1. A combined multi-stage gearbox, comprising: a spur-gear gearbox with at least one first and one second spur gear arranged on a spur-gear shaft; an epicyclic gearbox with at least one first and one second reduced, planetary gear set and with an epicyclic gearbox shaft, wherein at least one of the planetary gear sets is arranged concentrically with respect to the epicyclic gearbox shaft; a gearbox housing, wherein the spur-gear shaft and the epicyclic gearbox shaft are mounted so as to be rotatable relative to the gearbox housing; and a multiplicity of shift devices, wherein the first spur gear is selectively connectable in torque-conducting fashion to the spur-gear shaft, the first spur gear is selectively connectable in torque-conducting fashion to the gearbox housing, and only two shift devices are activated for at least one gearspeed stage.

2. The multi-stage gearbox according to claim 1, wherein the spur-gear shaft and the epicyclic gearbox shaft are, for power transmission from and to the multi-stage gearbox, designed such that the two gearbox shafts are arranged incongruently with respect to one another so as to be radially spaced apart from one another.

3. The multi-stage gearbox according to claim 1, wherein the second spur gear meshes with a third spur gear, and the third spur gear is selectively connectable in torque-conducting fashion to a sun gear of the first planetary gear set.

4. The multi-stage gearbox according to claim 3, wherein the third spur gear is selectively connectable in torque-conducting fashion to an internal gear of the first planetary gear set.

5. The multi-stage gearbox according to claim 4, wherein the first spur gear meshes with a fourth spur gear, and the fourth spur gear is connectable to the internal gear of the first planetary gear set.

6. The multi-stage gearbox according to claim 3, wherein the third spur gear is selectively connectable in torque-conducting fashion to the gearbox housing.

7. The multi-stage gearbox according to claim 3, wherein the third spur gear is selectively connectable in torque-conducting fashion to a planet gear carrier, at least of the first or of both planetary gear sets.

8. The multi-stage gearbox according to claim 1, wherein the first planetary gear set has at least one first planet gear, the second planetary gear set has at least one second planet gear, the first planet gear meshes with the second planet gear, and the first and the second planet gear are rotatably mounted on the planet gear carrier.

9. The multi-stage gearbox according to claim 8, wherein the planet gear carrier is selectively connectable in torque-conducting fashion to the gearbox housing.

10. The multi-stage gearbox according to claim 8, wherein at least one of the second planet gears meshes with a second sun pinion of the second planetary gear set, and an outer diameter of the second sun pinion of the second planetary gear set is greater than the outer diameter of a first sun pinion of the first planetary gear set, and the multi-stage gearbox has at least six shift devices.

11. The multi-stage gearbox according to claim 8, wherein at least one of the second planet gears meshes with a second sun pinion of the second planetary gear set, and an outer diameter of the second sun pinion (SO2) is smaller than an outer diameter of a first sun pinion of the first planetary gear set, and the multi-stage gearbox has at least six shift devices.

12. A drivetrain for a motor vehicle, comprising: a multi-stage gearbox according to claim 1, wherein the spur-gear shaft is couplable to a drive machine, the epicyclic gearbox shaft is couplable to a drive-output shaft, and by way of the drive-output shaft, drive power which is transmittable from the drive machine to the multi-stage gearbox is transmittable in a direction of at least one driveable wheel.

13. The multi-stage gearbox according to claim 1, wherein only two shift devices are activated for each gearspeed stage.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a schematic diagram of a longitudinal section through a combined seven-gearspeed multi-stage gearbox according to an embodiment of the invention.

(2) FIG. 2 is a shift diagram for a combined seven-gearspeed multi-stage gearbox of this type.

(3) FIG. 3 is a schematic diagram of a longitudinal section through a combined multi-stage gearbox according to an embodiment of the invention with six forward gearspeeds.

(4) FIG. 4 is a shift diagram for a combined six-gearspeed multi-stage gearbox of this type.

(5) FIG. 5 is a schematic diagram of a longitudinal section through a combined multi-stage gearbox according to an embodiment of the invention with six forward gearspeeds.

(6) FIG. 6 is a shift diagram for a combined six-gearspeed multi-stage gearbox of this type.

(7) FIG. 7 is a schematic diagram of a longitudinal section through a multi-stage gearbox according to an embodiment of the invention with seven forward gearspeeds and indirect coupling of the first spur gear to the gearbox housing.

(8) FIG. 8 is a schematic diagram of a longitudinal section through a combined multi-stage gearbox according to an embodiment of the invention with seven forward gearspeeds.

(9) FIG. 9 is a shift diagram for a combined six-gearspeed multi-stage gearbox of this type.

DETAILED DESCRIPTION OF THE DRAWINGS

(10) FIG. 1 illustrates a longitudinal section through a multi-stage gearbox. The multi-stage gearbox has a first sub-gearbox 1, which is in the form of a spur-gear gearbox, and a second sub-gearbox 2, which is in the form of an epicyclic gearbox device with two planetary gear sets (2a, 2b). The supply of power (rotational speed, torque) into the multi-stage gearbox is realized via the spur-gear shaft AN, and drive is output via the epicyclic gearbox shaft AB. The first sub-gearbox 1 has a first spur gear 1.1 and a second spur gear 1.2.

(11) The drive power (rotational speed, torque) is supplied to the multi-stage gearbox, and thus to the drivetrain, by way of the internal combustion engine VKM. By way of the multi-stage gearbox, the transmission ratio between the shafts AN/AB can be adapted, and the drive power can be output via the epicyclic gearbox shaft AB to the driveable wheels AR.

(12) The first spur gear 1.1 is selectively connectable in torque-conducting fashion to the spur-gear shaft AN by way of a torque-transmitting device 13 in which shift devices 1.SE and 3.SE are structurally combined. The first shift device 1. SE is designed to connect the first spur gear 1.1 to the gearbox housing 3.

(13) The shift device 3.SE is designed to connect the spur gear 1.1 to the sun pinion shaft AN. The spur gear 1.1 meshes with a fourth spur gear 1.4, and said fourth spur gear 1.4 is arranged coaxially with respect to the epicyclic gearbox shaft AB. The second spur gear 1.2 meshes with a third spur gear 1.3, and said third spur gear 1.3 is also arranged coaxially with respect to the epicyclic gearbox shaft AB. The third spur gear 1.3 has a torque-transmitting device 52, in which the shift devices 5.SE and 2.SE are structurally combined, and a further torque-transmitting device 47, in which the shift devices 4.SE and 7.SE are structurally combined.

(14) By way of the shift device 2.SE, the third spur gear 1.3 is connectable to the sun pinion shaft SO1 of the first planetary gear set 2a. By way of the shift device 5.SE, said sun pinion shaft SO1 is connectable to the gearbox housing 3. Here, the torque-transmitting device 52 is designed such that in each case only the shift device 2.SE or the shift device 5.SE is activatable. Here, the activation is to be understood to mean that a torque can be transmitted by the shift device.

(15) By way of the shift device 7.SE, the third spur gear 1.3 is connectable to the internal gear HO of the first planetary gear set 2a. The internal gear HO is arranged concentrically with respect to, and formed integrally with, the fourth spur gear 1.4. By way of the shift device 4.SE, the third spur gear 1.3 is connectable to the planet gear carrier PT of the epicyclic gearbox.

(16) Here, the torque-transmitting device 47 is designed such that either the shift device 4.SE or the shift device 7.SE is activatable.

(17) The first planet gears P1 and the second planet gears P2 are rotatably mounted on the planet gear carrier PT. The planet gears P1 and P2 are mounted on the planet gear carrier PT such that said planet gears mesh with one another. The first planet gears P1 furthermore mesh with the internal gear HO. The second planet gears P2 mesh with the sun pinion SO2 of the second planetary gear set 2b. The sun pinion SO2 of the second planetary gear set 2b has a smaller outer diameter than the sun pinion SO1 of the first planetary gear set 2a.

(18) The planet gear carrier PT has a torque-transmitting device 6, and the torque-transmitting device 6 has a shift device 6.SE, by way of which the planet gear carrier PT is connectable to the gearbox housing 3. If one of the gearbox elements is connected to the gearbox housing 3, specifically the sun pinion shaft SO1 by way of the shift device 5.SE, the planet gear carrier PT by way of the shift device 6.SE or the first spur gear 1.1 by way of the shift device 1.SE, said gearbox element is immobilized and has a rotational speed of zero. Through the selective coupling of said gearbox elements to the gearbox housing 3, on the one hand, and the selective coupling of gearbox elements to one another by way of the shift devices 2.SE, 4.SE and 3.SE, it is possible by way of said multi-stage gearbox to realize one reverse gearspeed and seven forward gearspeeds. Here, the torque-transmitting devices (6, 13, 47, 52) are designed such that in each case only two shift devices (1.SE to 7.SE) are activated for one gearspeed stage (reverse gearspeed and first to seventh gearspeed).

(19) FIG. 2 shows a shift diagram for a multi-stage gearbox according to the invention. In the table shown in FIG. 2, the greyed regions indicate that a shift device (1.SE to 7.SE) is activated. It can be seen from the shift diagram that in each case only two shift devices are activated for a respective gearspeed.

(20) FIG. 3 illustrates a longitudinal section through a multi-stage gearbox according to the invention with six shift stages. The multi-stage gearbox has a first sub-gearbox 1, which is in the form of a spur-gear gearbox, and a second sub-gearbox 2, which is in the form of an epicyclic gearbox device with two planetary gear sets (2a, 2b). The supply of power (rotational speed, torque) into the multi-stage gearbox is realized via the spur-gear shaft AN, and drive is output via the epicyclic gearbox shaft AB. The first sub-gearbox has a first spur gear 1.1 and a second spur gear 1.2.

(21) The drive power (rotational speed, torque) is supplied to the multi-stage gearbox, and thus to the drivetrain, by way of the internal combustion engine VKM. By way of the multi-stage gearbox, the transmission ratio between the shafts AN/AB can be adapted, and the drive power can be output via the epicyclic gearbox shaft AB to the driveable wheels AR.

(22) The first spur gear 1.1 is selectively connectable in torque-conducting fashion to the spur-gear shaft AN by way of a torque-transmitting device 13 in which shift devices 1.SE and 3.SE are structurally combined. The first shift device 1.SE is designed to connect the first spur gear 1.1 to the gearbox housing 3.

(23) The shift device 3. SE is designed to connect the spur gear 1.1 to the sun pinion shaft AN. The spur gear 1.1 meshes with a fourth spur gear 1.4, and said fourth spur gear 1.4 is arranged coaxially with respect to the epicyclic gearbox shaft AB. The second spur gear 1.2 meshes with a third spur gear 1.3, and said third spur gear 1.3 is also arranged coaxially with respect to the epicyclic gearbox shaft AB. The third spur gear 1.3 has a torque-transmitting device 42, in which the shift devices 4.SE and 2.SE are structurally combined, and a further torque-transmitting device 6, in which the shift device 6.SE is accommodated.

(24) By way of the shift device 2.SE, the third spur gear 1.3 is connectable to the sun pinion shaft SO1 of the first planetary gear set 2a. By way of the shift device 4.SE, said sun pinion shaft SO1 is connectable to the gearbox housing 3. Here, the torque-transmitting device 42 is designed such that in each case only the shift device 2.SE or the shift device 4.SE is activatable.

(25) By way of the shift device 6.SE, the third spur gear 1.3 is connectable to the internal gear HO of the first planetary gear set 2a. The internal gear HO is arranged concentrically with respect to, and formed integrally with, the fourth spur gear 1.4.

(26) The first planet gears P1 and the second planet gears P2 are rotatably mounted on the planet gear carrier PT. The planet gears P1 and P2 are mounted on the planet gear carrier PT so as to mesh with one another. The first planet gears P1 furthermore mesh with the internal gear HO. The second planet gears P2 mesh with the sun pinion SO2 of the second planetary gear set 2b. The sun pinion SO2 of the second planetary gear set 2b has a larger outer diameter than the sun pinion SO1 of the first planetary gear set 2a.

(27) The planet gear carrier PT has a torque-transmitting device 5, and the torque-transmitting device 5 has a shift device 5.SE, by way of which the planet gear carrier PT is connectable to the gearbox housing 3. If one of the gearbox elements is connected to the gearbox housing 3, specifically the sun pinion shaft SO1 by way of the shift device 4.SE, the planet gear carrier PT by way of the shift device 5.SE or the first spur gear 1.1 by way of the shift device 1.SE, said gearbox element is immobilized and has a rotational speed of zero. Through the selective coupling of said gearbox elements to the gearbox housing 3, on the one hand, and the selective coupling of gearbox elements to one another by way of the shift devices 2.SE, 3.SE and 6.SE, it is possible by way of said multi-stage gearbox to realize one reverse gearspeed and six forward gearspeeds. Here, the torque-transmitting devices (5, 6, 13, 42) are designed such that in each case only two shift devices (1.SE to 6.SE) are activated for one gearspeed stage (reverse gearspeed and first to sixth gearspeed).

(28) FIG. 4 shows a shift diagram for a six-gearspeed multi-stage gearbox according to the invention. In the table shown in FIG. 4, the greyed regions indicate that a shift device (1.SE to 6.SE) is activated. It can be seen from the shift diagram that in each case only two shift devices are activated for a respective gearspeed.

(29) FIG. 5 illustrates a longitudinal section through a multi-stage gearbox according to the invention with six shift stages. The multi-stage gearbox has a first sub-gearbox 1, which is in the form of a spur-gear gearbox, and a second sub-gearbox 2, which is in the form of an epicyclic gearbox device with two planetary gear sets (2a, 2b). The supply of power (rotational speed, torque) into the multi-stage gearbox is realized via the spur-gear shaft AN, and drive is output via the epicyclic gearbox shaft AB. The first sub-gearbox has a first spur gear 1.1 and a second spur gear 1.2.

(30) The drive power (rotational speed, torque) is supplied to the multi-stage gearbox, and thus to the drivetrain, by way of the internal combustion engine VKM. By way of the multi-stage gearbox, the transmission ratio between the shafts AN/AB can be adapted, and the drive power can be output via the epicyclic gearbox shaft AB to the driveable wheels AR.

(31) The first spur gear 1.1 is selectively connectable in torque-conducting fashion to the spur-gear shaft AN by way of a torque-transmitting device 13 in which shift devices 1.SE and 3.SE are structurally combined. The first shift device 1.SE is designed to connect the first spur gear 1.1 to the gearbox housing 3.

(32) The shift device 3.SE is designed to connect the spur gear 1.1 to the sun pinion shaft AN. The spur gear 1.1 meshes with a fourth spur gear 1.4, and said fourth spur gear 1.4 is arranged coaxially with respect to the epicyclic gearbox shaft AB. The second spur gear 1.2 meshes with a third spur gear 1.3, and said third spur gear 1.3 is also arranged coaxially with respect to the epicyclic gearbox shaft AB. The third spur gear 1.3 has a torque-transmitting device 52, in which the shift devices 5.SE and 2.SE are structurally combined, and a further torque-transmitting device 46, in which the shift devices 6.SE and 4.SE are structurally combined.

(33) By way of the shift device 2.SE, the third spur gear 1.3 is connectable to the sun pinion shaft SO1 of the first planetary gear set 2a. By way of the shift device 5.SE, said sun pinion shaft SO1 is connectable to the gearbox housing 3. Here, the torque-transmitting device 52 is designed such that in each case only the shift device 2.SE or the shift device 5.SE is activatable.

(34) By way of the shift device 6.SE, the third spur gear 1.3 is connectable to the internal gear HO of the first planetary gear set 2a. The internal gear HO is arranged concentrically with respect to, and formed integrally with, the fourth spur gear 1.4. By way of the shift device 4.SE, the third spur gear is selectively connectable in torque-conducting fashion to the planet gear carrier PT of the first and second planetary gear sets 2b.

(35) The first planet gears P1 and the second planet gears P2 are rotatably mounted on the planet gear carrier PT. The planet gears P1 and P2 are mounted on the planet gear carrier PT so as to mesh with one another. Furthermore, the first planet gears P1 mesh with the internal gear HO. The second planet gears P2 mesh with the sun pinion SO2 of the second planetary gear set 2b. The sun pinion SO2 of the second planetary gear set 2b has a larger outer diameter than the sun pinion SO1 of the first planetary gear set 2a.

(36) In this embodiment, all shift devices 1.SE to 6.SE are structurally combined in each case in pairwise fashion in torque-transmitting devices 13, 46 and 52, and particularly simple actuation thereof is realized, and furthermore, a reduced structural space requirement can be achieved, because in each case only one (2-way) sliding sleeve is used for two shift devices.

(37) If one of the gearbox elements is connected to the gearbox housing 3, specifically the sun pinion shaft SO1 by way of the shift device 5.SE or the first spur gear 1.1 by way of the shift device 1.SE, said gearbox element is immobilized and has a rotational speed of zero. Through the selective coupling of said gearbox elements to the gearbox housing 3, on the one hand, and the selective coupling of gearbox elements to one another by way of the shift devices 2.SE, 3.SE, 4.SE and 6.SE, it is possible by way of said multi-stage gearbox to realize one reverse gearspeed and six forward gearspeeds. Here, the torque-transmitting devices (13, 46, 52) are designed such that in each case only two shift devices (1.SE to 6.SE) are activated for one gearspeed stage (reverse gearspeed and first to sixth gearspeed).

(38) FIG. 6 shows a shift diagram for a six-gearspeed multi-stage gearbox according to the invention. In the table shown in FIG. 6, the greyed regions indicate that a shift device (1.SE to 6.SE) is activated. It can be seen from the shift diagram that in each case only two shift devices are activated for a respective gearspeed.

(39) FIG. 7 substantially illustrates the multi-stage gearbox known from FIG. 5, such that the differences between said gearboxes will be discussed below. The first spur gear 1.1 is firstly selectively connectable in torque-conducting fashion by way of the torque-transmitting device 3 and the shift device 3.SE to the spur-gear shaft AN. Furthermore, indirect coupling of the first spur gear 1.1 is made possible by way of the torque-transmitting device 1a and the shift element 1.SE.

(40) For a multi-stage gearbox as illustrated in FIG. 7, the shift diagram known from FIG. 6 can be used for the control thereof.

(41) FIG. 8 illustrates a longitudinal section through a multi-stage gearbox according to the invention. The multi-stage gearbox has a first sub-gearbox 1, which is in the form of a spur-gear gearbox, and a second sub-gearbox 2, which is in the form of an epicyclic gearbox device with two planetary gear sets (2a, 2b). The supply of power (rotational speed, torque) into the multi-stage gearbox is realized via the spur-gear shaft AN, and drive is output via the epicyclic gearbox shaft AB; here, the epicyclic gearbox shaft is concentric with respect to the axis of rotation of the third and fourth spur gears (1.3, 1.4). The first sub-gearbox has a first spur gear 1.1 and a second spur gear 1.2.

(42) The drive power (rotational speed, torque) is supplied to the multi-stage gearbox, and thus to the drivetrain, by way of the internal combustion engine VKM. By way of the multi-stage gearbox, the transmission ratio between the shafts AN/AB can be adapted, and the drive power can be output via the epicyclic gearbox shaft AB to the driveable wheels AR.

(43) The first spur gear 1.1 is selectively connectable in torque-conducting fashion to the spur-gear shaft AN by way of a torque-transmitting device 13 in which shift devices 1.SE and 3.SE are structurally combined. The first shift device 1.SE is designed to connect the first spur gear 1.1 to the gearbox housing 3.

(44) The shift device 3.SE is designed to connect the spur gear 1.1 to the sun pinion shaft AN. The spur gear 1.1 meshes with a fourth spur gear 1.4, and said fourth spur gear 1.4 is arranged coaxially with respect to the epicyclic gearbox shaft AB. The second spur gear 1.2 meshes with a third spur gear 1.3, and said third spur gear 1.3 is also arranged coaxially with respect to the epicyclic gearbox shaft AB. The third spur gear 1.3 has a torque-transmitting device 42, in which the shift devices 4.SE and 2.SE are structurally combined, and a further torque-transmitting device 67, in which the shift devices 6.SE and 7.SE are structurally combined.

(45) By way of the shift device 2.SE, the third spur gear 1.3 is connectable to the sun pinion shaft SO1 of the first planetary gear set 2a. By way of the shift device 4.SE, said sun pinion shaft SO1 is connectable to the gearbox housing 3. Here, the torque-transmitting device 42 is designed such that in each case only the shift device 2.SE or the shift device 4.SE is activatable. Here, the activation is to be understood to mean that a torque can be transmitted by the shift device.

(46) By way of the shift device 7.SE, the third gearwheel 1.3 is connectable to the internal gear HO1 of the first planetary gear set 2a. The internal gear HO is arranged concentrically with respect to, and formed integrally with, the fourth spur gear 1.4, ring-shaped gearwheel with an external toothing (1.4) and an internal toothing (HO). By way of the shift device 6.SE, the third spur gear 1.3 is connectable to the planet gear carrier PT of the epicyclic gearbox (common planet gear carrier).

(47) Here, the torque-transmitting device 67 is designed such that either the shift device 6.SE or the shift device 7.SE is activatable.

(48) The first planet gears P1 and the second planet gears P2 are rotatably mounted on the planet gear carrier PT. The planet gears P1 and P2 are mounted on the planet gear carrier PT so as to mesh with one another. Furthermore, the first planet gears P1 mesh with the internal gear HO and the sun pinion shaft SO1. The second planet gears P2 mesh with the sun pinion SO2 of the second planetary gear set 2b, and the second planetary gear set 2b furthermore does not have a dedicated internal gear (reduced planetary gear set). The sun pinion SO2 of the second planetary gear set 2b has a larger outer diameter than the sun pinion SO1 of the first planetary gear set 2a.

(49) The planet gear carrier PT has a torque-transmitting device 5, and the torque-transmitting device 5 has a shift device 5.SE by way of which the planet gear carrier PT is connectable to the gearbox housing 3. If one of the gearbox elements is connected to the gearbox housing 3, specifically the sun pinion shaft SO1 by way of the shift device 4.SE, the planet gear carrier PT by way of the shift device 5.SE or the first spur gear 1.1 by way of the shift device 1.SE, said gearbox element is immobilized and has a rotational speed of zero. Through the selective coupling of said gearbox elements to the gearbox housing 3, on the one hand, and the selective coupling of gearbox elements to one another by way of the shift devices 2.SE, 3.SE, 6.SE and 7.SE, it is possible by way of said multi-stage gearbox to realize one reverse gearspeed and seven forward gearspeeds. Here, the torque-transmitting devices (5, 13, 42, 67) are designed such that in each case only two shift devices (1.SE to 7.SE) are activated for one gearspeed stage (reverse gearspeed and first to seventh gearspeed).

(50) FIG. 9 shows a shift diagram for a multi-stage gearbox according to the invention. In the table shown in FIG. 9, the greyed regions indicate that a shift device (1.SE to 7.SE) is activated. It can be seen from the shift diagram that in each case only two shift devices are activated for a respective gearspeed.

(51) The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.