Method for controlling an automated motor vehicle transmission

• US 9,020,717 B2
• Filed: 07/03/2014
• Issued: 04/28/2015
• Est. Priority Date: 07/29/2013
• Status: Expired due to Fees

• Current Assignee: ZF Friedrichshafen AG (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Original Assignee: ZF Friedrichshafen AG (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Inventors: Kemler, Johannes, Wuerthner, Maik, Staudinger, Joachim
• Primary Examiner(s): Wright, Dirk
• Application Number:
  US14/322,958
• Publication Number:
  US 20150032346A1
• Time in Patent Office: 299 Days
• Field of Search: None
• US Class Current: 701/65
• CPC Class Codes: F16H 2059/142 of driving resistance calculated from weight, slope, or the like
• CPC Class Codes: F16H 2061/0234 Adapting the ratios to special vehicle conditions
• CPC Class Codes: F16H 61/0204 for gearshift control, e.g. control functions for performing shifting or generation of shift signal
• CPC Class Codes: F16H 61/0213 characterised by the method for generating shift signals
• CPC Class Codes: F16H 61/70 specially adapted for change-speed gearing in group arrangement, i.e. with separate change-speed gear trains arranged in series, e.g. range or overdrive-type gearing arrangements

Abstract

A method of controlling an automated motor vehicle transmission. A current driving resistance is taken into account when selecting a target gear to be engaged as part of a shifting process. In order to be able to regulate shifting processes in a driving-resistance-dependent manner so as to ensure that the motor vehicle can always able to continue driving on, during selection of the target gear, disregarding gears for shifting from a currently engaged gear, in a driving-resistance-dependent manner, when the required associated shifting times are longer than a respective permitted maximum shifting time. In connection with the above, the method is incorporated in an automated motor vehicle transmission, a computer program product and a data carrier, containing the computer program product.

Claims

1. A method of controlling an automated motor vehicle transmission (1), the method comprising the steps of:

taking into account a current driving resistance when selecting a target gear (G_reg, G′

) to be engaged as part of a shifting process, and

during selecting the target gear (G_reg, G′

) to be engaged, disregarding, in a driving resistance-dependent manner, gears for shifting from a currently engaged gear with shifting times (t_{G reg}) that are longer than a respective permitted maximum shifting time (t_zul(α

, m)).

2. The method according to claim 1, further comprising the step of, if the motor vehicle transmission comprises a group configuration, disregarding, in a driving resistance-dependent manner, gears whose engagement entails individual shifts in a plurality of transmission groups and, therefore, requires shifting times (t_G.reg) longer than the permitted maximum shifting time (t_zul(α

, m)).

3. The method according to claim 1, further comprising the step of disregarding gears only up to a gear limit (G_Grenz(α

, m)), beyond which the target gear (G_reg, G′

) is selected independently of shifting times.

4. The method according to claim 3, further comprising the step of setting the gear limit (G_Grenz(α

, m)) as a function of the driving resistance , having regard to a road inclination (α

) and a vehicle mass (m).

5. The method according to claim 1, further comprising the step of besides disregarding gears with shifting times (t_G.reg) longer than the permitted maximum shifting time (t_zul(α

, m), disregarding gears which, if engaged, a traction force (F_{zug, G′}

) provided by a drive engine (AM) connected upstream from the motor vehicle transmission (1) would be insufficient for the driving resistance at the time.

6. The method according to claim 5, further comprising the step of, after disregarding those gears that are to be disregarded, preventing a gearshift out of the currently engaged gear when no selectable gear remain available for the gearshift.

7. The method according to claim 1, further comprising the step of determining, during previous shifts, the shifting times (t_{G reg}) required in each case for shifting out of the current gear to other gears.

8. The method according to claim 1, further comprising the step of operating the method in an automated motor vehicle transmission (1).

9. A computer program for of an automated motor vehicle transmission (1) which is operated in accordance with a method of controlling an automated motor vehicle transmission (1), the method comprising the steps of:

taking into account a current driving resistance when selecting a target gear (G_reg, G′

) to be engaged as part of a shifting process, and during selecting the target gear (G_reg, G′

) to be engaged, disregarding, in a driving resistance-dependent manner, gears for shifting from a currently engaged gear with shifting times (t_G.reg) that are longer than a respective permitted maximum shifting time (t_zul(α

, m));

wherein a routine for carrying out a gearshift in the automated motor vehicle transmission (1) is implemented by corresponding control commands stored in a software system.

10. The computer program product of the automated motor vehicle transmission (1) according to according to claim 9, wherein the computer program product is stored on a computer-readable storage medium.

11. A method of controlling an automated transmission of a motor vehicle, the method comprising the steps of:

initiating a gearshift from a currently engaged gear to a target gear;

determining a current driving resistance of the motor vehicle;

considering, from possible targets gears to be selected, at least one potential target gear;

removing the potential target gear from consideration as the target gear, if, based on the current driving resistance, a required amount of time to shift from the currently engaged gear to the potential target gear exceeds a respective permitted maximum shifting time; and

selecting the considered potential target gear as the target gear for the gearshift.