Process for controlling an automatic transmission
AssigneeZF Friedrichshafen AG
InventorsHans-Jorg Domian, Ralf Dreibholz, Gerd Frotscher, Thomas Schober
Life of this patent
Estimating the term…
Abstract
A process is proposed for controlling an automatic transmission where changing from one gear speed to another is brought about as a result of a first clutch (11) opening and a second clutch (12) closing. It is further proposed to apply the process to a group transmission.
Claims15
A process for controlling an automatic transmission driven by an internal combustion engine wherein a change from a first to a second gear speed is brought about as result of a first clutch (11) disengaging and a second clutch (12) engaging, an electronic control device controls, via more than one electromagnetic valve, a pressure curve of said first (11) and second (12) clutches during a gearshifting operation, the electronic control device selects, on the basis of input variables, one of a first or a second gearshifting method, the first gearshifting method being one of an upshift for pulling load or a downshift for pushing load and the second gearshifting method being one of a downshift for pulling load or an upshift for pushing load, the gearshifting operations comprising the steps of:
- providing a rapid filling phase;
- following the rapid filling phase by a filling equalizing phase;
- following the filling equalizing phase by a load take-over phase;
- following the load take-over phase by a gradient setting phase;
- following the gradient setting phase by a sliding phase;
- following the sliding phase by a gradient breakdown phase;
- and
- following the gradient breakdown phase by a closure phase;
- wherein during the first gearshifting method the load take-over phase (3) is followed by the gradient setting phase (4) with the sliding phase (5), and the gradient breakdown phase (6) precedes the closure phase (8);
- and during the second gearshifting method the filling equalizing phase (2) is followed by the gradient setting phase (4) with the sliding phase (5) and the gradient breakdown phase (6) proceeds the load take-over phase (7).
A process for controlling an automatic transmission in a group design driven by an internal combustion engine wherein a change from a first to a second gear speed is achieved by shifting devices in first (19) and a second (20) transmission parts working in opposite directions, said first transmission part having a large ratio range and said second transmission part a small ratio range, and, in each transmission part, a first clutch (11) disengages and a second clutch (12) engages, an electronic control device controlling during a gearshift operation, via more than one electromagnetic valve, a start of the gearshift operation and a pressure curve of said first (11) and second (12) clutches of said first (19) and second (20) transmission parts, said electronic control device selecting, on the basis of input variables, one of a first or a second gearshifting method, the first gearshifting method being an upshift for pulling load or a downshift for pushing load and said second gearshifting method being one of a downshift for pulling load or an upshift for pushing load, the automatic transmission being simultaneously shifted in the first and second transmission parts, the gearshifting operations comprising the steps of:
- providing a rapid filling phase;
- following the rapid filling phase by a filling equalizing phase;
- following the filling equalizing phase by a load take-over phase;
- following-the load take-over phase by a gradient setting phase;
- following the gradient setting phase by a sliding phase;
- following the sliding phase by a gradient breakdown phase;
- and
- following the gradient breakdown phase by a closure phase;
- wherein during the first gearshifting method the load take-over phase (3) is followed by the gradient setting phase (4) with the sliding phase (5), and the gradient breakdown phase (6) precedes the closure phase (8);
- and during the second gearshifting method the filling equalizing phase (2) is followed by the gradient setting phase (4) with the sliding phase (5) and the gradient breakdown phase (6) proceeds the load take-over phase (7).
Dependencies are inferred from the claim text.