Stopping position control apparatus and stopping position control method of internal combustion engine

Abstract

A stopping position control apparatus of an internal combustion engine includes an engine friction model for calculating the friction around a crankshaft, which calculates friction in the internal combustion engine, and a transmission friction model for calculating the friction around the crankshaft, which calculates friction in a transmission. When a clutch arranged between the internal combustion engine and the transmission is engaged, a crankshaft stopping position is calculated based on the friction calculated by both the engine friction model and the transmission friction model.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and further objects, features and advantages of the invention will become apparent from the following description of preferred embodiments with reference to the accompanying drawings, wherein like numerals are used to represent like elements and wherein:

FIG. 1 is a view of the structure of an internal combustion engine to which a stopping position control apparatus of an internal combustion engine according to a first example embodiment of the invention is applied;

FIG. 2 is a block diagram of the structure of an engine model provided in an ECU shown in FIG. 1;

FIG. 3 is a view showing reference characters of each element around the crankshaft;

FIGS. 4A and 4B are graphs showing an example of engine friction maps for obtaining engine friction torque TRQ_f—EN, which are provided in the engine friction model shown in FIG. 2;

FIG. 5 is a graph showing an example of a transmission friction map for obtaining transmission friction torque TRQ_f—m, which is provided in the transmission friction model shown in FIG. 2;

FIGS. 6A and 6B are views illustrating a method according to a modified example for obtaining the history of an cylinder internal pressure P;

FIG. 7 is a flowchart of a routine executed in the first example embodiment;

FIG. 8 is a graph illustrating a method for calculating friction difference ΔTRQ_f;

FIG. 9 is an example of a map for obtaining a friction distribution ratio R(dθ/dt); and

FIG. 10 is a flowchart of a routine executed in a modified example embodiment of the invention.

Claims

1. A stopping position control apparatus of an internal combustion engine, comprising: a transmission;an engine friction model that calculates friction in the internal combustion engine;a transmission friction model that calculates friction in a transmission used in combination with the internal combustion engine;a clutch engagement state detecting device that detects whether a clutch arranged between the internal combustion engine and the transmission is engaged; anda crankshaft stopping position calculating device that calculates a position where a crankshaft of the internal combustion engine is stopped,wherein when the clutch is engaged, a crankshaft stopping position is calculated based on the friction calculated by both the engine friction model and the transmission friction model.

2. The stopping position control apparatus of an internal combustion engine according to claim 1, further comprising: a deviation contributing degree obtaining apparatus that obtains, based on crank angle information of the internal combustion engine, each degree of contribution that the engine friction model and the transmission friction model each contribute to deviation in the crankshaft stopping position due to friction; anda deviation distributing apparatus that distributes, based on the degree of contribution, the deviation in the crank stopping position to the engine friction model.

3. The stopping position control apparatus of an internal combustion engine according to claim 2, further comprising: a friction correcting apparatus that corrects the engine friction model and/or the transmission friction model based on the distributed deviation in the crankshaft stopping position.

4. The stopping position control apparatus of an internal combustion engine according to claim 1, further comprising: a correcting information obtaining apparatus that obtains information as to whether the engine friction model and/or the transmission friction model has been corrected while the clutch is engaged,wherein the deviation contributing degree obtaining apparatus includes a contributing degree correcting device that corrects the degree of contribution if the deviation in the crankshaft stopping position is determined to be larger than a predetermined value when the crankshaft stopping position is calculated while the clutch is disengaged after the engine friction model and/or the transmission friction model has been corrected while the clutch is engaged.

5. The stopping position control apparatus of an internal combustion engine according to claim 1, further comprising: a transmission friction obtaining apparatus that obtains transmission friction corresponding to the friction in the transmission by separating the transmission friction corresponding to the friction in the transmission from the total friction that is calculated by both the engine friction model and the transmission friction model;a first friction learning apparatus which performs learning of the engine friction model and the transmission friction model in combination or performs only learning of the engine friction model; anda second friction learning apparatus that performs learning, independently of the first friction learning apparatus, of the transmission friction model based on the transmission friction.

6. A stopping position control method of an internal combustion engine, comprising the steps of: calculating friction in the internal combustion engine based on an engine friction model;calculating friction in a transmission used in combination with the internal combustion engine based on a transmission friction model;detecting whether a clutch that is arranged between the internal combustion engine and the transmission is engaged; andcalculating a crankshaft stopping position based on the friction calculated by the engine friction model and the transmission friction model, when the clutch is engaged.

7. The stopping position control method of an internal combustion engine according to claim 6, further comprising the steps of: obtaining, based on crank angle information of the internal combustion engine, each degree of contribution that the engine friction model and the transmission friction model each contribute to deviation in the crankshaft stopping position due to friction; anddistributing the deviation in the crank stopping position between the engine friction model and the transmission friction model based on the degree of contribution.

8. The stopping position control method of an internal combustion engine according to claim 7, further comprising the step of: correcting the engine friction model and/or the transmission friction model based on the distributed deviation in the crankshaft stopping position.

9. The stopping position control method of an internal combustion engine according to claim 6, further comprising the steps of: obtaining information as to whether the engine friction model and/or the transmission friction model has been corrected while the clutch is engaged; andcorrecting the degree of contribution if the deviation in the crankshaft stopping position is determined to be larger than a predetermined value when the crankshaft stopping position is calculated while the clutch is disengaged after the engine friction model and/or the transmission friction model has been corrected while the clutch is engaged.

10. The stopping position control method of an internal combustion engine according to claim 6, further comprising the steps of: obtaining transmission friction corresponding to the friction in the transmission by separating the transmission friction corresponding to the friction in the transmission from the total friction that is calculated by both the engine friction model and the transmission friction model;performing learning of the engine friction model and the transmission friction model in combination or performs only learning of the engine friction model; andperforming learning, independently of the first friction learning, of the transmission friction model based on the transmission friction.

11. A stopping position control apparatus of an internal combustion engine, comprising: a transmission;an engine friction model that calculates friction in the internal combustion engine;a transmission friction model that calculates friction in the transmission used in combination with the internal combustion engine;a crankshaft stopping position calculating means for calculating a position where a crankshaft of the internal combustion engine is stopped,a clutch engagement state detecting device that detects whether a clutch arranged between the internal combustion engine and the transmission is engaged,wherein when the clutch is engaged, a crankshaft stopping position is calculated based on the friction calculated by both the engine friction model and the transmission friction model.