System and method for increasing upshift engine torque

Patent metadata

Field	Value
Publication number	US-11718302-B2
Application number	US-202017097260-A
Country	US
Kind code	B2
Filing date	Nov 13, 2020
Priority date	Nov 15, 2019
Publication date	Aug 8, 2023
Grant date	Aug 8, 2023

Abstract

A drive train control method includes transmitting a total time period of a stroke phase and a torque phase of an upshift from a transmission control unit of an automatic transmission to an engine control unit of an engine. The method also includes closing a first shift element of the automatic transmission and opening a second shift element of the automatic transmission during the upshift. A control pressure of the first shift element increases during the torque phase relative to the control pressure of the first shift element at an end of the stroke phase. A control pressure of the second shift element decreases during the torque phase relative to the control pressure of the second shift element at the end of the stroke phase. The method further includes, based at least in part on the total time period of the stroke and torque phases, increasing an actual torque of the engine during the upshift such that the actual torque of the engine increases to a higher gear torque prior to an end of the torque phase.

First claim

What is claimed is:

1. A drive train control method, comprising:
transmitting a total time period of a stroke phase and a torque phase of an upshift from a transmission control unit of an automatic transmission to an engine control unit of an engine;
closing a first shift element of the automatic transmission during the upshift, a control pressure of the first shift element increasing during the torque phase relative to the control pressure of the first shift element at an end of the stroke phase;
opening a second shift element of the automatic transmission during the upshift, a control pressure of the second shift element decreasing during the torque phase relative to the control pressure of the second shift element at the end of the stroke phase;
increasing a target torque of the engine during the torque phase, the target torque of the engine begins increasing prior to an end of the stroke phase; and
based at least in part on the total time period of the stroke and torque phases, increasing an actual torque of the engine during the upshift such that the actual torque of the engine increases to a higher gear torque prior to an end of the torque phase.

2. The drive train control method of claim 1 , wherein the first and second shift elements are in a slip torque transmission state during the torque phase of the upshift.

3. The drive train control method of claim 1 , wherein the upshift further comprises an inertia phase, and a speed of the engine decreases during the inertia phase.

4. The drive train control method of claim 3 , wherein the first and second shift elements are in a slipping torque transmission state during the torque phase of the upshift, the first shift element is closed during the inertia phase of the upshift, and the second shift element is open during the inertia phase of the upshift.

5. The drive train control method of claim 3 , wherein the torque phase immediately follows the stroke phase in the upshift, and the inertia phase immediately follows the torque phase in the upshift.

6. The drive train control method of claim 1 , wherein increasing the target torque of the engine begins after a time delay from a start of the upshift, and the time delay is no less than one hundred and fifty milliseconds and no greater than four hundred milliseconds.

7. The drive train control method of claim 1 , wherein increasing the target torque of the engine begins about seventy milliseconds prior to the end of the stroke phase.

8. The drive train control method of claim 1 , wherein the torque phase immediately follows the stroke phase in the upshift.

9. The drive train control method of claim 1 , wherein a longitudinal acceleration of a vehicle with the automatic transmission and the engine is substantially constant during the upshift.

10. The drive train control method of claim 1 , wherein the total time period of the stroke and torque phases is calculated by the transmission control unit based at least in part on one or more of a temperature of the automatic transmission, an input shaft speed of the automatic transmission, and a target torque of the engine.

11. The drive train control method of claim 1 , wherein the total time period of the stroke and torque phases is one of a plurality of predetermined total time periods saved in a memory of the transmission control unit.

12. The drive train control method of claim 11 , further comprising selecting the one of the plurality of predetermined total time periods based at least in part on one or more of a temperature of the automatic transmission, an input shaft speed of the automatic transmission, and a target torque of the engine.

13. A control system for a drive train with an automatic transmission and an engine, comprising:
a transmission control unit of the automatic transmission;
an engine control unit of the engine; and
a communication bus, the transmission control unit in communication with the engine control unit via the communication bus;
wherein the transmission and engine control units are configured to transmit a total time period of a stroke phase and a torque phase of an upshift from the transmission control unit to the engine control unit,
wherein the transmission control unit is configured to close a first shift element of the automatic transmission and open a second shift element of the automatic transmission during the upshift, a control pressure of the first shift element increasing during the torque phase relative to the control pressure of the first shift element at an end of the stroke phase, a control pressure of the second shift element decreasing during the torque phase relative to the control pressure of the second shift element at the end of the stroke phase,
wherein the engine control unit is further configured to increase a target torque of the engine during the torque phase, the engine control unit configured to start increasing the target torque of the engine after a time delay from a start of the upshift, the time delay being no less than one hundred and fifty milliseconds and no greater than four hundred milliseconds, and
wherein the engine control unit is configured to, based at least in part on the total time period of the stroke and torque phases, increase an actual torque of the engine with the engine control unit during the upshift such that the actual torque of the engine increases to a higher gear torque prior to an end of the torque phase.

14. The control system of claim 13 , wherein the total time period of the stroke and torque phases is calculated by the transmission control unit based at least in part on one or more of a temperature of the automatic transmission, an input shaft speed of the automatic transmission, and a target torque of the engine.

15. The control system of claim 13 , wherein the total time period is a one of a plurality of predetermined total time periods saved in a memory of the transmission control unit, and the transmission control unit is further configured to select the one of the plurality of predetermined total time periods based at least in part on one or more of a temperature of the automatic transmission, an input shaft speed of the automatic transmission, and a target torque of the engine.

16. A drive train control method, comprising:
transmitting one or both of a time period of a stroke phase of an upshift and a time period of a torque phase of the upshift from a transmission control unit of an automatic transmission to an engine control unit of an engine;
closing a first shift element of the automatic transmission during the upshift, a control pressure of the first shift element increasing during the torque phase relative to the control pressure of the first shift element at an end of the stroke phase;
opening a second shift element of the automatic transmission during the upshift, a control pressure of the second shift element decreasing during the torque phase relative to the control pressure of the second shift element at the end of the stroke phase; and
based at least in part on the one or both of the time periods of the stroke and torque phases, increasing a target torque of the engine during the upshift such that an actual torque of the engine increases to a higher gear torque prior to an end of the torque phase,
wherein the target torque of the engine begins increasing prior to an end of the stroke phase.

17. The drive train control method of claim 16 , wherein increasing the target torque of the engine begins after a time delay from a start of the upshift, and the time delay is no less than one hundred and fifty milliseconds and no grea

Assignees

• Zahnradfabrik Friedrichshafen
• Honda Motor Co Ltd

Inventors

• Mohr Frieder
• Villing Christian
• Stark Thomas
• Shitani Yoshitaka
• Tucker Matthew J
• Gokan Yasuhiro
• Hopp Christopher
• Mori Ryuichi
• Kobayashi Makoto
• Murata Ryuji

Classifications

• B60W30/19 Primary

  Improvement of gear change, e.g. by synchronisation or smoothing gear shift · CPC title

• B60W10/02

  including control of driveline clutches · CPC title

• B60W10/06

  including control of combustion engines · CPC title

• B60W10/11

  Stepped gearings · CPC title

• F16H61/00

  Control functions within {control units of} change-speed- or reversing-gearings for conveying rotary motion {; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing} · CPC title