Power-split continuously variable transmission device

Abstract

A variator unit is fixed to a rotationally fixed component and has a secondary side rotationally fixed to an input shaft and a primary side rotationally fixed to a first element of a first planetary gear set. The input shaft is rotationally fixable via a second shift element to a second element of a second planetary gear set, which is fixable to the rotationally fixed component via a first shift element, and is rotationally fixed to a first element of a third planetary gear set. A second element of the first planetary gear set is fixed to the rotationally fixed component. A first element of the second planetary gear set is rotationally fixed to a third element of the third planetary gear set. A third element of the first planetary gear set is rotationally fixed to a third element of the second planetary gear set.

Claims

1. A power-split continuously variable transmission device (100), comprising: an input shaft (1); an output shaft (2); a first planetary gear set (RS1) arranged between the input shaft (1) and the output shaft (2); a second planetary gear set (RS2) connected to the first planetary gear set (RS1) and arranged between the input shaft (1) and the output shaft (2); a third planetary gear set (RS3) connected to the second planetary gear set (RS2) and arranged between the input shaft (1) and the output shaft (2); and a variator unit (10) for transmitting power in a continuously variable manner from the input shaft (1) to the first planetary gear set (RS1), the variator unit (10) having a first shift element (B1), a second shift element (K1) and a third shift element (K2), selective actuation of the first, second and third shift elements (B1, K1, K2) providing different power paths between the input shaft (1) and the output shaft (2) while making a first mode (FB1), a second mode (FB2) and a third mode (FB3) available, wherein the variator unit (10) is fixed to a rotationally fixed component (GG), a primary side (11) of the variator unit (10) is rotationally fixed to the input shaft (1), and a secondary side (12) of the variator unit (10) is rotationally fixed to a first element (E11) of the first planetary gear set (RS1), wherein the input shaft (1) is rotationally fixable to a second element (E22) of the second planetary gear set (RS2) via the second shift element (K1), and the input shaft (1) is rotationally fixed to a first element (E31) of the third planetary gear set (RS3), wherein a second element (E12) of the first planetary gear set (RS1) is fixed to the rotationally fixed component (GG), wherein the second element (E22) of the second planetary gear set (RS2) is fixable to the rotationally fixed component (GG) via the first shift element (B1), wherein a first element (E21) of the second planetary gear set (RS2) is rotationally fixed to a third element (E33) of the third planetary gear set (RS3), wherein a third element (E13) of the first planetary gear set (RS1) is rotationally fixed to a third element (E23) of the second planetary gear set (RS2), wherein a second element (E32) of the third planetary gear set (RS3) is rotationally fixed to the output shaft (2) and is rotationally fixable to the third element (E13) of the first planetary gear set (RS1) and the third element of the second planetary gear set (RS2) via the third shift element (K2).

2. The transmission device (100) of claim 1, wherein the first, second and third planetary gear sets (RS1, RS2, RS3) are arranged axially adjacent to one another.

3. The transmission device (100) of claim 1, wherein the second planetary gear set (RS2) is arranged radially outside the third planetary gear set (RS3).

4. The transmission device (100) of claim 1, wherein: the first mode (FB1) is continuously variable power-split and implemented when the first shift element (B1) is engaged, the second mode (FB2) is continuously variable variator-driven and implemented when the third shift element (K2) is engaged, and the third mode (FB3) is continuously variable power-split and implemented when the second shift element (K1) is engaged.

5. The transmission device (100) of claim 1, further comprising an electric machine (EM), a rotor (R) of the electric machine (EM) connected to the input shaft (1), the output shaft (2) or another shaft (3, 4, 5, 6).

6. The transmission device (100) of claim 5, further comprising a separating clutch, the input shaft (1) being rotationally fixable to a connecting shaft via the separating clutch.

7. The transmission device (100) of claim 5, wherein the electric machine (EM) is arranged coaxially to the input shaft (1).

8. The transmission device (100) of claim 5, wherein the electric machine (EM) is arranged axially parallel to the input shaft (1).

9. A motor vehicle drive train comprising the transmission device (100) of claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention is explained in greater detail with reference to the following figures. In the figures, the following is shown:

(2) FIG. 1 shows a schematic view of a transmission device according to the invention in a preferred first embodiment;

(3) FIG. 2 shows a schematic view of a transmission device according to the invention in a preferred second embodiment;

(4) FIG. 3 shows a shift pattern of the transmission device according to FIG. 1;

(5) FIG. 4 shows a schematic view of a transmission device according to the invention in a preferred third embodiment;

(6) FIG. 5 shows a schematic view of a transmission device according to the invention in a preferred fourth embodiment;

(7) FIG. 6 shows a schematic view of a transmission device according to the invention in a preferred fifth embodiment;

(8) FIG. 7 shows a schematic view of a transmission device according to the invention in a preferred sixth embodiment;

(9) FIG. 8 shows a schematic view of a transmission device according to the invention in a preferred further embodiment;

(10) FIG. 9 shows a schematic view of a transmission device according to the invention in a preferred further embodiment;

(11) FIG. 10 shows a schematic view of a transmission device according to the invention in a preferred further embodiment;

(12) FIG. 11 shows a schematic view of a transmission device according to the invention in a preferred further embodiment;

(13) FIG. 12 shows a schematic view of a transmission device according to the invention in a preferred further embodiment; and

(14) FIG. 13 shows a schematic view of a transmission device according to the invention in a preferred further embodiment.

DETAILED DESCRIPTION

(15) Reference will now be made to embodiments of the invention, one or more examples of which are shown in the drawings. Each embodiment is provided by way of explanation of the invention, and not as a limitation of the invention. For example, features illustrated or described as part of one embodiment can be combined with another embodiment to yield still another embodiment. It is intended that the present invention include these and other modifications and variations to the embodiments described herein.

(16) FIG. 1 shows a schematic of a power-split continuously variable transmission device 100 in the form of a mechanical IVT transmission which, in the area of an input shaft 1, is operatively connected directly, i.e., without a coupling device, to a drive machine (not represented). The drive machine is an internal combustion engine in the form of a diesel engine or a gas engine.

(17) A torque which is made available by the drive machine and is present in the area of the input shaft 1 is guidable along multiple power paths, wherein a variator 10 is provided for varying a ratio of the respective power path, whereby the overall gear ratio of the transmission device 100 is continuously variable to the desired extent via the variator 10.

(18) The shares of the torque present on the transmission input side in the area of the input shaft 1, which are guided along the power paths, are guided in the direction of the output shaft 2.

(19) The transmission 100 further includes a first shift element B1, a second shift element K1, and a third shift element K2 and one first planetary gear set RS1 connected to the variator 10. The transmission 100 also includes a second planetary gear set RS2 which is connected to the first planetary gear set RS1. The transmission 100 also includes a third planetary gear set RS3 which is connected to the second planetary gear set RS2. The first shift element B1 is a brake and each of the second and third shift elements K1 and K2 is a clutch. The variator 10, the first, second, and third shift elements B1, K1 and K2, and the first, second, and third planetary gear sets RS1, RS2 and RS3 are arranged between the input shaft 1 and the output shaft 2 of the transmission 100. The first, second, and third planetary gear sets RS1, RS2 and RS3 are simple (minus) planetary gear sets.

(20) The following nomenclature applies for a minus planetary gear set: the first element of the minus planetary gear set is a sun gear, the second element of the minus planetary gear set is a planet carrier, i.e., carrier, and the third element of the minus planetary gear set is a ring gear.

(21) The first planetary gear set RS1 includes a first element E11, a second element E12, and a third element E13, wherein the first element E11 is a sun gear SO1, the second element E12 is a planet carrier or carrier PT1, and the third element E13 is a ring gear HO1.

(22) In a known way, the sun gear SO1 intermeshes with one or several planet gears PR1 which are rotatably mounted on the planet carrier PT1 and intermesh with the ring gear HO1, and so, with the planet carrier PT1 held and the sun gear SO1 rotating, the ring gear HO1 rotates in the direction of rotation counter to that of the sun gear SO1. The carrier PT1 is permanently fixed on a rotationally fixed component, a transmission housing GG, which is marked by reference sign 0.

(23) The second planetary gear set RS2 includes a first element E21, a second element E22, and a third element E23, wherein the first element E21 is a sun gear SO2, the second element E22 is a planet carrier or carrier PT2, and the third element E23 is a ring gear HO2.

(24) In a known way, the sun gear SO2 intermeshes with one or several planet gears PR2 which are rotatably mounted on the planet carrier PT2 and intermesh with the ring gear HO2, and so, with the planet carrier PT2 held and the sun gear SO2 rotating, the ring gear HO2 rotates in the direction of rotation counter to that of the sun gear SO2.

(25) The third planetary gear set RS3 includes a first element E31, a second element E32, and a third element E33, wherein the first element E31 is a sun gear 503, the second element E32 is a planet carrier or carrier PT3, and the third element E33 is a ring gear HO3.

(26) In a known way, the sun gear SO3 intermeshes with one or several planet gears PR3 which are rotatably mounted on the planet carrier PT3 and, for their part, intermesh with the ring gear HO3, and so, with the planet carrier PT3 held and the sun gear SO3 rotating, the ring gear HO3 rotates in the direction of rotation counter to that of the sun gear SO3.

(27) The variator 10 is a planetary roller variator. As is known, a planetary roller variator has a primary side 11 and a secondary side 12. In addition, the planetary roller variator is fastened, i.e., fixed to the transmission housing GG. The primary side 11 is rotationally connected to the input shaft 1 of the transmission 100.

(28) The secondary side 12 of the variator 10 is rotationally fixed via a third shaft 3 to the sun gear SO1 of the first planetary gear set RS1. In addition, the input shaft 1 is rotationally fixable via the clutch K1 to the sixth shaft 6 and, therefore, to the carrier PT2 of the second planetary gear set RS2. In addition, the input shaft 1 is rotationally fixed to the sun gear SO3.

(29) The ring gear HO2 is rotationally fixed via a fifth shaft 5 to the ring gear HO1. The ring gear HO3 is rotationally fixed to the sun gear SO2 via a fourth shaft 4. The carrier PT3 is rotationally fixed to the output shaft 2.

(30) When the brake B1 is actuated, i.e., engaged, the carrier PT1 is rotationally fixed to the carrier PT2 which is fixed on the transmission housing GG and, therefore, is prevented from turning. When the clutch K1 is engaged, the input shaft 1 is rotationally fixed to the sixth shaft 6 and, therefore, to the carrier PT2. When the clutch K2 is engaged, the ring gears HO1 and HO2, i.e., the fifth shaft 5, are rotationally fixed to the carrier PT3, i.e., to the output shaft.

(31) In this case, three ranges of ratios, i.e., first mode FB1, second mode FB2, and third mode FB3 for forward travel, is implementable in the transmission device 100 by selective control of the first, second and third shift elements B1, K1 and K2, wherein the first mode FB1 is reversible, i.e., is implementable as a reverse mode, by adjusting the variator 10. The changeover between the modes takes place by the alternate opening and closing of two of the first, second, and third shift elements at a speed-synchronized point.

(32) The first, second, and third planetary gear sets RS1, RS2 and RS3 are arranged axially adjacent to each other in order to enable the transmission device 100 to be arranged in an installation-space-favorable manner in the radial direction. The first planetary gear set RS1 is arranged axially between the variator 10 and the second planetary gear set RS2. The second planetary gear set RS2 is arranged axially between the first planetary gear set RS1 and the third planetary gear set RS3. The transmission 100 according to FIG. 1 is in a standard arrangement including a coaxial driven end.

(33) Through the selection of suitable ratios, the sun gear SO3 (via the drive machine, fixed ratio) and the ring gear HO3 (via the variator, infinitely variable ratio) of the third planetary gear set RS3 are operable at the same circumferential speed, although in opposite directions, and so the output carrier PT3 is at a standstill, i.e., the rotational speed of the output carrier PT3 is zero (geared neutral). If the rotational speed of the ring gear HO3 is changed by an adjustment of the variator ratio, the carrier PT3 begins to turn. The vehicle starts. In this way, a launch clutch is omitted in an advantageous way.

(34) In contrast to FIG. 1, the transmission according to FIG. 2 is a so-called front-transverse arrangement including a lateral driven end.

(35) FIG. 3 shows a shift pattern of the transmission device 100, in table form. As shown in the shift pattern, in order to implement the first range of ratios, i.e. the first mode FB1, for forward travel, the first shift element B1 is to be engaged, while the second and third shift elements K1 and K2 are in the disengaged operating condition. If there is an appropriate demand for implementing the second range of ratios, i.e. the second mode FB2, for forward travel, the first shift element B1 is to be disengaged if the first mode FB1 for forward travel is presently engaged, the third shift element K2 is to be engaged, and the second shift element K1 is left in the disengaged operating condition. However, if there is an appropriate demand for implementing the third range of ratios, i.e. the third mode FB3, for forward travel, the second shift element K1 is to be engaged, the third shift element K2 is transferred into the disengaged operating condition, and the first shift element B1 is kept in the disengaged operating condition. As described above, the second and third shift elements K1 and K2 are clutches and the first shift element B1 is a brake.

(36) The reverse operation is implemented via the first mode FB1, in that the variator 10 is adjusted, i.e., reversed.

(37) When the first range of ratios, the first mode FB1, for forward travel or travel in reverse is engaged, a lesser first share of the torque introduced into the transmission device 100 via the input shaft 1 is guided via the variator 10 in the direction of the output shaft 2 and a greater second share of the torque is guided into the third planetary gear set RS3 via the direct connection of the input shaft 1 to the sun gear SO3. Therefore, the power flow in the first range of ratios FB1 takes place in a power-split manner.

(38) When the third range of ratios, third mode FB3, for forward travel is engaged, a lesser first share of the torque introduced into the transmission device 100 via the input shaft 1 is also guided via the variator 10 in the direction of the output shaft 2 and a greater second share of the torque is guided into the second planetary gear set RS2 via the clutch K1 and into the third planetary gear set RS3 via the direct connection to the sun gear SO3. Therefore, the power flow in the third range of ratios FB3 takes place in a power-split manner.

(39) When the second range of ratios, second mode FB2, for forward travel is engaged, the total torque introduced into the transmission device 100 via the input shaft 1 is guided via the variator 10 in the direction of the output shaft 2 without power splitting, whereby the second range of ratios FB2 is a so-called direct mode, the spread of gear ratios of which corresponds to the spread of gear ratios of the variator 10.

(40) A ratio of the transmission device 100 is continuously variable within each of the first, second, and third modes FB1, FB2 and FB3 via the variator 10.

(41) FIG. 4 shows the transmission in a nested gear set arrangement, i.e., the second planetary gear set RS2 is arranged radially outside the third planetary gear set RS3. This is possible due to the fixed sun gear-ring gear coupling, i.e., the fixed connection between the sun gear SO2 of the second planetary gear set RS2 and the ring gear HO3 of the third planetary gear set RS3. As a result, an axially even more compact version of the transmission 100 is possible.

(42) In contrast to FIG. 4, the transmission according to FIG. 5 is a so-called front-transverse arrangement including a lateral driven end.

(43) FIG. 6 shows the transmission device 100 in one further embodiment. The transmission 100 includes a plus planetary gear set, wherein the second planetary gear set RS2 is the plus planetary gear set.

(44) The following nomenclature applies for a plus planetary gear set: the first element is the sun gear, the second element is the ring gear, and the third element is the planet carrier, i.e., the carrier.

(45) In FIG. 6, the second planetary gear set RS2 includes the same sun gear SO2, inner planet gears PR21, and outer planet gears PR22, which are rotatably mounted on the carrier PT2 (third element E23), and a ring gear HO2 (second element E22). Due to the interchange, the carrier PT2 of the second planetary gear set RS2 is connected to the ring gear HO1 of the first planetary gear set RS1 and via the clutch K2 to the carrier PT3. When the brake B1 is actuated, the carrier PT1 of the first planetary gear set RS1 is rotationally fixed to the ring gear HO2 of the second planetary gear set RS2. When the clutch K1 is engaged, the input shaft 1 is rotationally fixed to the ring gear HO2 of the second planetary gear set RS2. The transmission 100 according to FIG. 6 is in a standard arrangement including a coaxial driven end.

(46) A transmission device in which each of the first and the second planetary gear sets is a minus planetary gear set and the third planetary gear set is a plus planetary gear set is not represented, but is also preferred.

(47) In contrast to FIG. 6, the transmission according to FIG. 7 is a so-called front-transverse arrangement including a lateral driven end.

(48) FIGS. 8 to 13 show the transmission 100 in a hybrid application in three embodiments. The input shaft 1, in particular, is suitable for the connection of an electric machine EM.

(49) The transmission according to FIG. 8 includes an electric machine EM, the stator S of which is rotationally fixed to the rotationally fixed component GG, while a rotor R of the electric machine EM is rotationally fixed to the input shaft 1. Moreover, the input shaft 1 is rotationally fixable, at the mounting interface 1-A, via an intermediate separating clutch K0 which is configured as a lamellar shift element in this case, to a connecting shaft AN which, in turn, is connected to a crankshaft of the drive machine (not represented). Due to the rotationally fixed connection of the rotor R to the input shaft 1, the electric machine EM is located coaxially to the input shaft 1.

(50) Purely electric driving is implementable via the electric machine EM, wherein, in this case, the separating clutch K0 is disengaged in order to decouple the input shaft 1 from the connecting shaft AN and to not entrain the internal combustion engine. All continuously variable modes are utilizable electrically. A start into the internal combustion engine-driven modes is always possible. For the rest, the embodiment according to FIG. 8 corresponds to the variant according to FIG. 1, and therefore reference is made to the description thereof.

(51) In contrast to FIG. 8, the transmission according to FIG. 11 is a so-called front-transverse arrangement including a lateral driven end.

(52) Moreover, FIG. 9 shows a schematic view of a transmission 100 according to a further design option of the invention, which largely corresponds to the preceding variant represented in FIG. 8. The difference is that the electric machine EM is not arranged coaxially, but rather axially offset with respect to the input shaft 1. Consequently, a rotor (not represented in detail in this case) of the electric machine EM and the input shaft 1 are also not connected to each other in a rotationally fixed manner, but rather are coupled to each other via an intermediate spur gear stage SRS. In this case, a first spur gear SR1 of the spur gear stage SRS is located on the input shaft 1 in a rotationally fixed manner and intermeshes with a second spur gear SR2 which is arranged, in a rotationally fixed manner, on an input shaft EW of the electric machine EM. This input shaft EW then establishes the connection to the rotor within the electric machine EM.

(53) For the rest, the embodiment according to FIG. 9 corresponds to the variant according to FIG. 8, and therefore reference is made to the description thereof.

(54) In contrast to FIG. 9, the transmission according to FIG. 12 is a so-called front-transverse arrangement including a lateral driven end.

(55) In addition, FIG. 10 shows a schematic of a transmission 100 according to a further embodiment of the invention, which also essentially corresponds again to the variant according to FIG. 8. As is already the case with the embodiment according to FIG. 9, the electric machine EM is not arranged coaxially, however, but rather axially offset with respect to the input shaft 1. A rotationally fixed coupling between the input shaft 1 and a rotor (not represented) of the electric machine EM is achieved in this case via a flexible traction drive mechanism ZT which is preferably present as a chain drive. This flexible traction drive mechanism ZT couples the input shaft 1 to an input shaft EW of the electric machine EM in this case. Otherwise, the variant according to FIG. 10 corresponds to the embodiment according to FIG. 8, and therefore reference is made to the description thereof.

(56) In contrast to FIG. 10, the transmission according to FIG. 13 is a so-called front-transverse arrangement including a lateral driven end.

(57) The hybrid application has been described with reference to the embodiment according to FIG. 1. The remaining embodiments can also be hybridized, of course, i.e., also the embodiments according to FIGS. 2 to 7. The plus planetary gear set variants, which are not represented but which have been described, are also appropriate for a hybrid application.

(58) With the aid of the embodiments according to the invention, a transmission having a compact design and good efficiency is implementable.

(59) Modifications and variations can be made to the embodiments illustrated or described herein without departing from the scope and spirit of the invention as set forth in the appended claims.

REFERENCE CHARACTERS

(60) 1 input shaft 2 output shaft, second shaft 3 third shaft 4 fourth shaft 5 fifth shaft 6 sixth shaft 10 variator unit, variator, planetary roller variator 11 primary side variator unit 12 secondary side variator unit 100 power-split continuously variable transmission device, continuously variable planetary transmission An connecting shaft B1 first shift element, brake E11 first element E12 second element E13 third element E21 first element E22 second element E23 third element E31 first element E32 second element E33 third element EM electric machine FB1 first mode, forward or in reverse FB2 second mode, forward FB2 third mode, forward HO1 first ring gear HO2 second ring gear HO3 third ring gear K0 separating clutch K1 second shift element, clutch K2 third shift element, clutch PR1 planet gear PR2 planet gear PR3 planet gear PR21 inner planet gear PR22 outer planet gear PT1 first planet gear carrier, carrier PT2 second planet gear carrier, carrier PT3 third planet gear carrier, carrier RS1 first planetary gear set RS2 second planetary gear set RS3 third planetary gear set R rotor S stator SO1 first sun gear SO2 second sun gear SO3 third sun gear SRS spur gear stage SR1 spur gear SR2 spur gear ZT flexible traction drive mechanism