Method and system for a vehicle

Patent metadata

Field	Value
Publication number	US-10190511-B2
Application number	US-201214119284-A
Country	US
Kind code	B2
Filing date	Jun 7, 2012
Priority date	Jun 10, 2011
Publication date	Jan 29, 2019
Grant date	Jan 29, 2019

Abstract

A method for running a vehicle (100) that includes a combustion engine (101) which can selectively be connected to a driveshaft (104, 105). When the vehicle (100) is in motion and is approaching a downgrade, determining whether the engine (101) can be disconnected from the driveshaft (104, 105) for at least a first period of time (T1), and disconnecting the driveshaft (104, 105) for at least the first period of time (T1); and the engine (101) also is switched off for the first period (T1). A system that performs the method and a vehicle that performs it are disclosed.

First claim

The invention claimed is:

1. A method for running a vehicle having a combustion engine, a starter motor and a driveshaft to which the engine is selectively connected to deliver driving force to the driveshaft for propulsion of the vehicle when the vehicle is in motion, the method comprising:
determining that the vehicle is approaching a downgrade within a period of time or within a specified distance;
in response to the determination that the vehicle is approaching a downgrade, determining, based on look ahead data obtained for the vehicle, a look ahead data-based freewheel period of time, the look ahead data-based freewheel period of time being at least a period during which the vehicle is on the downgrade;
determining whether the look ahead data-based freewheel period of time is at least as long as a predetermined first period of time such that an amount of fuel reduction when the engine is switched off for the entirety of the first period of time is at least a first predetermined amount of fuel consumed when the engine is started by the starter motor; and
only when the determination is made that the look ahead data-based freewheel period of time is at least as long as the predetermined first period of time, disconnecting the engine from the driveshaft for the entirety of the look ahead data-based freewheel period, and switching off the engine for the entirety of the look ahead data-based freewheel period.

2. A method according to claim 1 , wherein the fuel reduction for vehicle operation when the engine is switched off during the first period of time is equal to or greater than an amount of fuel consumption required when the engine is started by a starter motor.

3. A method according to claim 1 , wherein the first predetermined amount of fuel is greater than or equal to:
an amount of fuel consumption required for starting the engine by the starter motor plus any amount of fuel corresponding to electrical energy used to run the starter motor plus the first amount of fuel to compensate for wear on engine and vehicle components caused by the engine starting and stopping upon the disconnection of the engine from the driveshaft.

4. A method according to claim 1 , wherein the determining whether the engine should be disconnected from the driveshaft for at least the entirety of the first period of time is based on at least one of data concerning an itinerary ahead of the vehicle including road gradients of the itinerary, and
data concerning a road topography of the itinerary ahead of the vehicle, and
the vehicle's location.

5. A method according to claim 1 , further comprising activating a cruise control function for the vehicle configured for setting a speed of the vehicle upon the determining of whether the engine should be disconnected from the driveshaft for the entirety of the first period of time.

6. A method according to claim 1 , wherein the vehicle is permitted to freewheel by disconnecting the engine and the driveshaft and switching off the engine, and the method further comprises:
restarting the engine by connecting the engine to the driveshaft.

7. A method according to claim 1 , further comprising:
when determining that the engine should be disconnected from the driveshaft, making an engine restart determination comprising determining whether to restart the engine by engaging a starter motor or by connecting the engine to the driveshaft,
wherein the engine restart determination is based on data concerning an itinerary ahead of the vehicle,
wherein the first predetermined amount of fuel includes an amount of fuel consumption required for starting the engine by a starter motor plus an amount of fuel corresponding to electrical energy used to run the starter motor.

8. The method according to claim 7 , wherein the restart determination is made before the determining of whether the engine should be disconnected from the driveshaft for at least the first period of time.

9. A method according to claim 1 , wherein the vehicle further comprises a gearbox which is configured to be set to a first number of fixed gear ratios; and
when the engine is to be connected to the driveshaft, determining which of the fixed gear ratios is to be set in the gearbox based on data concerning an itinerary ahead of the vehicle.

10. A method according to claim 1 , wherein the determining whether the engine should be disconnected from the driveshaft for at least a first period of time is performed by a control unit situated in a control system of the vehicle.

11. A method according to claim 10 , wherein the first period of time is at least two seconds.

12. A non-transitory computer-readable medium incorporating program code which, when the program code is executed in a computer, causes the computer to apply the method according to claim 1 .

13. A system for running a vehicle with a combustion engine which is selectively connected to a driveshaft for the engine to deliver driving force to the driveshaft for propulsion of the vehicle, and a starter motor, the system comprising:
a look ahead device configured to determine that the vehicle is approaching a downgrade within a period of time or within a specified distance;
a freewheeling period determining device configured to determine, when the vehicle is in motion and in response to the determination that the vehicle is approaching a downgrade, based on look ahead data obtained for the vehicle, a look ahead data-based freewheeling period of time, the look ahead data-based freewheel period of time being a period during which the vehicle is on the downgrade;
determining whether the look ahead data-based freewheel period of time is at least as long as a predetermined first period of time such that an amount of fuel reduction for the vehicle operation when the engine is switched off for the entirety of the first period of time is at least a first predetermined amount of fuel consumed when the engine is started by the starter motor; and
a disconnect device configured to disconnect, only when the determining device determines that the look ahead data-based freewheel period of time is at least as long as the predetermined first period of time, disconnecting the engine from the driveshaft for at least the entirety of the look ahead data-based freewheel period of time and switching off the engine for the entirety of the look ahead data-based freewheel period of time.

14. A system according to claim 13 , wherein the device for disconnecting the engine from the driveshaft opens a clutch of the vehicle and/or puts the gearbox into a neutral state.

15. A vehicle including a system according to claim 13 .

16. A vehicle according to claim 15 , further comprising a steering servo which operates substantially independently of rotation of the engine's output shaft.

17. A vehicle according to claim 15 , further comprising the starter motor, the starter motor more powerful than a starter motor of a vehicle of similar size and capacity.

18. The vehicle according to claim 15 , wherein the first period of time is a period during which the vehicle is on a downgrade.

Assignees

• Abdul Rasool Mustafa
• Johansson Oskar
• Oegren Mikael
• Scania Cv Ab

Inventors

• Abdul-Rasool Mustafa
• Johansson Oskar
• Ögren Mikael

Classifications

• B60W2030/1809

  Without torque flow between driveshaft and engine, e.g. with clutch disengaged or transmission in neutral · CPC title

• B60W2710/1005

  Transmission ratio engaged · CPC title

• B60W50/0097 Primary

  Predicting future conditions · CPC title

• B60W10/30

  including control of auxiliary equipment, e.g. air-conditioning compressors or oil pumps · CPC title

• B60W10/11

  Stepped gearings · CPC title