Gearbox for a hybrid powertrain and method to control the gearbox

Patent metadata

Field	Value
Publication number	US-9541167-B2
Application number	US-201414780016-A
Country	US
Kind code	B2
Filing date	Mar 20, 2014
Priority date	Mar 27, 2013
Publication date	Jan 10, 2017
Grant date	Jan 10, 2017

Abstract

A gearbox that includes an input shaft ( 8 ) and an output shaft ( 20 ); a first epicyclic gear ( 10 ) that is connected to the input shaft ( 8 ); a second epicyclic gear ( 12 ) that is connected to the first epicyclic gear ( 10 ); a first electrical machine ( 14 ) that is connected to the first epicyclic gear ( 10 ); a second electrical machine ( 16 ) that is connected to the second epicyclic gear ( 12 ); a first gear pair ( 60 ) that is arranged between the first epicyclic gear ( 10 ) and the output shaft ( 20 ); and a second gear pair ( 66 ) that is arranged between the second epicyclic gear ( 12 ) and the output shaft ( 20 ). A side shaft ( 18 ) is arranged between one of the epicyclic gears ( 10, 12 ) and the output shaft ( 20 ) ( 18 ) and connected to the output shaft ( 20 ) through a final gear, ( 21 ) ( 21 ) which includes a gear element ( 92 ), that is arranged at the side shaft ( 18 ) in a disengagable manner. Also, disclosed is a method for controlling the gearbox. Also a vehicle ( 1 ) that includes such a gearbox ( 2 ), and a method to control such a gearbox ( 2 ). Also a computer program (P) to control a gearbox ( 2 ).

First claim

The invention claimed is:

1. A gearbox comprising an input shaft and an output shaft;
a first epicyclic gear that is connected to the input shaft;
a second epicyclic gear that is connected to the first epicyclic gear;
a first electrical machine that is connected to the first epicyclic gear;
a second electrical machine that is connected to the second epicyclic gear;
a first gear pair that is arranged between the first epicyclic gear and the output shaft;
a second gear pair that is arranged between the second epicyclic gear and the output shaft;
a second main shaft connected to the second epicyclic gear;
a second planet gear carrier at the second epicyclic gear that is connected to the second main shaft; and
a side shaft arranged between the respective first and second epicyclic gears and the output shaft, wherein
the input shaft is connected to the first planet gear carrier;
the side shaft is connected to the output shaft through a final gear; and
the final gear comprises a gear element that is disengagably engaged at the side shaft.

2. The gearbox according to claim 1 , wherein a first main shaft is connected to the first epicyclic gear;
wherein the first gear pair is arranged at the first main shaft and the side shaft; and
wherein the second gear pair is arranged at the second main shaft and the side shaft.

3. The gearbox according to claim 2 , wherein a first planet gear carrier at the first epicyclic gear is connected to a second sun gear at the second epicyclic gear;
and wherein a first sun gear at the first epicyclic gear is connected to the first main shaft.

4. The gearbox according to claim 2 , wherein a coupling mechanism is arranged between the first main shaft and the output shaft.

5. The gearbox according to claim 2 , wherein the first gear pair comprises a first cogged wheel drive and a first cogged wheel that interact with each other, which first cogged wheel drive is fixed arranged with the first main shaft and the first cogged wheel being disengagably engaged to the side shaft-and wherein;
the second gear pair comprises a second cogged wheel drive and a second cogged wheel that interact with each other, the second cogged wheel drive being fixed to the second main shaft and the second cogged wheel being disengagably engaged to the side shaft.

6. The gearbox according to claim 5 , further comprising, a third gear pair that is arranged between the first epicyclic gear and the output shaft, the third gear pair comprising a third cogged wheel drive and a third cogged wheel that interact with each other, the third cogged wheel drive being fixed to the first main shaft and the third cogged wheel being disengagably engaged at the side shaft;
and a fourth gear pair that is arranged between the second epicyclic gear and the output shaft; the fourth gear pair comprising a fourth cogged wheel drive and a fourth cogged wheel that interact with each other, the fourth cogged wheel drive being fixed to the second main shaft and the fourth cogged wheel being disengagably engaged at the side shaft.

7. The gearbox according to claim 1 , wherein the gear element is disengagabley engaged at the side shaft with a fifth coupling element.

8. The gearbox according to claim 1 , wherein the gear element of the final gear is a fifth cogged wheel, that interacts with a sixth cogged wheel, that is fixed to the output shaft.

9. The gearbox according to claim 6 , wherein the first, second, third and fourth cogged wheels are disengagably engaged at the side shaft with first, second, third and fourth coupling elements.

10. The gearbox according to claim 1 , wherein a first rotor at the first electrical machine is connected to a first ring gear at the first epicyclic gear; and
a second rotor at the second electrical machine is connected to a second ring gear at the second epicyclic gear.

11. The gearbox according to claim 3 , wherein a first coupling unit separably connects the first sun gear to the first planet gear carrier; and
a second coupling unit separably connects the second sun gear to the second planet gear carrier.

12. The gearbox according to claim 11 , wherein a third coupling unit separably connects the first ring gear at the first epicyclic gear to a gear housing that surrounds the gear housing; and
a fourth coupling unit separably connects a second ring gear at the second epicyclic gear to the gear housing.

13. A vehicle, comprising an engine, and a gearbox according to claim 1 .

14. A method to control a gearbox, the gearbox including, an input shaft and an output shaft;
a first epicyclic gear that is connected to the input shaft;
a second epicyclic gear that is connected to the first epicyclic gear;
a first electrical machine that is connected to the first epicyclic gear;
a second electrical machine that is connected to the second epicyclic gear;
a first gear pair that is arranged between the first epicyclic gear and the output shaft; and
a second gear pair that is arranged between the second epicyclic gear and the output shaft, wherein a second main shaft is connected to the second epicyclic gear, a second planet gear carrier at the second epicyclic gear is connected to the second main shaft, and the input shaft is connected to the first planet gear carrier, the method comprising:
a) disengaging a gear element that is arranged at a side shaft and that is connected through a final gear to the output shaft;
b) transferring torque from the second epicyclic gear to the side shaft through the second gear pair; and
c) transferring torque from the side shaft to the output shaft through the first gear pair.

15. The method according to claim 14 , further comprising:
d) driving the second electrical machine with electrical energy generated from the first electrical machine in order to reduce with the second electrical machine the reactive torque from the second epicyclic gear, and to reduce the torque transferred at the second gear pair; and
e) increasing with the first electrical machine the reactive torque from the first epicyclic gear, in order to increase the torque transferred at the first gear pair.

16. The method according to claim 15 , further comprising:
f) disengaging with a first coupling unit a first sun gear arranged at the first epicyclic gear and a first planet gear carrier from each other; and
g) connecting with a fourth coupling unit a second ring gear arranged at the second epicyclic gear and a gear housing to each other.

17. The method according to claim 14 , wherein a reduction and an increase in reactive torque at the first and second electrical machines are synchronized, such that the torque at the output shaft is constant or changes in a continuous manner.

18. A computer product comprising:
a non-transitory computer readable medium and program code stored on the medium to carry out the method according to claim 14 , when the program code is run on an electronic control unit or another computer connected to the electronic control unit.

Assignees

• Scania Cv Ab

Inventors

• Lindström Johan
• Björkman Mathias
• Pettersson Niklas
• Bergquist Mikael

Classifications

• F16H2200/2064

  using at least one positive clutch, e.g. dog clutch · CPC title

• B60K6/40

  characterised by the assembly or relative disposition of components · CPC title

• Y10S903/911

  with two or more gear sets · CPC title

• F16H3/006

  power being selectively transmitted by parallel flow paths, e.g. dual clutch transmissions · CPC title

• Y02T10/6239

  Cross-Sectional Technologies · mapped topic