Device and method for controlling internal combustion engine

Abstract

When an ignition switch is turned off, an ECU executes a program including the steps of: stopping an engine; setting a phase of an intake camshaft (or a phase in which an intake valve opens/closes) to be a maximally retarded phase; advancing the phase of the intake camshaft; detecting the phase of the intake camshaft as based on a number or rotations of an electric motor of an intake VVT mechanism changing the phase of the intake camshaft; and, if the phase detected as based on the number or rotations of the electric motor is advanced to a target phase, stopping changing the phase of the intake camshaft.

1 . A control device for an internal combustion engine provided with a mechanism changing a phase in which at least one valve of an intake valve and an exhaust valve opens/closes, comprising an operation unit, wherein:
 said operation unit controls said mechanism to change said phase when a predetermined condition associated with stopping said internal combustion engine is satisfied;   said operation unit detects an amount by which said mechanism is operated when said mechanism is controlled to change said phase;   said operation unit detects said phase based on said amount; and   said operation unit controls said mechanism to change said phase detected as based on said amount to attain a predetermined value.   
   
   
       2 . The control device for an internal combustion engine according to  claim 1 , wherein said operation unit controls said mechanism to change said phase after said internal combustion engine is stopped if said predetermined condition is satisfied. 
   
   
       3 . The control device for an internal combustion engine according to  claim 1 , wherein:
 said mechanism includes a motor electrically operated and having an output shaft rotating to change said phase in which said valve opens/closes; and   said operation unit detects a number of rotations of said output shaft of said motor accumulated and detects said phase as based on said number of rotations of said output shaft of said motor accumulated.   
   
   
       4 . A control device for an internal combustion engine provided with a mechanism changing a phase in which at least one valve of an intake valve and an exhaust valve opens/closes, comprising an operation unit, wherein:
 said operation unit controls said mechanism to change said phase to attain a limit value when a predetermined condition associated with stopping said internal combustion engine is satisfied, said limit value being one of values of maximally retarded and advanced angles, respectively;   said operation unit controls said mechanism to change said phase from said limit value if said predetermined condition is satisfied;   said operation unit detects an amount by which said mechanism is operated when said mechanism is controlled to change said phase from said limit value;   said operation unit detects said phase based on said amount; and   said operation unit controls said mechanism to change said phase detected as based on said amount to attain a predetermined value.   
   
   
       5 . The control device for an internal combustion engine according to  claim 4 , wherein:
 said operation unit controls said mechanism to change said phase to said limit value after said internal combustion engine is stopped if said predetermined condition is satisfied; and   said operation unit controls said mechanism to change said phase from said limit value after said internal combustion engine is stopped if said predetermined condition is satisfied.   
   
   
       6 . The control device for an internal combustion engine according to  claim 4 , wherein:
 said mechanism includes a motor electrically operated and having an output shaft rotating to change said phase in which said valve opens/closes; and   said operation unit detects a number of rotations of said output shaft of said motor accumulated and detects said phase as based on said number of rotations of said output shaft of said motor accumulated.   
   
   
       7 . A method of controlling an internal combustion engine provided with a mechanism changing a phase in which at least one valve of an intake valve and an exhaust valve opens/closes, comprising the steps of:
 controlling said mechanism to change said phase when a predetermined condition associated with stopping said internal combustion engine is satisfied;   detecting an amount by which said mechanism is operated when said mechanism is controlled to change said phase; and   detecting said phase based on said amount, wherein   the step of controlling said mechanism includes the step of controlling said mechanism to change said phase detected in the step of detecting said phase to attain a predetermined value.   
   
   
       8 . The method of controlling an internal combustion engine according to  claim 7 , wherein the step of controlling said mechanism includes the step of controlling said mechanism to change said phase after said internal combustion engine is stopped if said predetermined condition is satisfied. 
   
   
       9 . The method of controlling an internal combustion engine according to  claim 7 , wherein:
 said mechanism includes a motor electrically operated and having an output shaft rotating to change said phase in which said valve opens/closes;   the step of detecting said amount includes the step of detecting a number of rotations of said output shaft of said motor accumulated; and   the step of detecting said phase includes the step of detecting said phase as based on said number of rotations of said output shaft of said motor accumulated.   
   
   
       10 . A method of controlling an internal combustion engine provided with a mechanism changing a phase in which at least one valve of an intake valve and an exhaust valve opens/closes, comprising the steps of:
 controlling said mechanism to change said phase to a limit value when a predetermined condition associated with stopping said internal combustion engine is satisfied, said limit value being one of values of maximally retarded and advanced angles, respectively;   controlling said mechanism to change said phase from said limit value when said predetermined condition is satisfied,   detecting an amount by which said mechanism is operated when said mechanism is controlled to change said phase from said limit value; and   detecting said phase based on said amount, wherein   the step of controlling said mechanism to change said phase from said limit value includes the step of controlling said mechanism to change said phase detected as based on said amount to attain a predetermined value.   
   
   
       11 . The method of controlling an internal combustion engine according to  claim 10 , wherein:
 the step of controlling said mechanism to change said phase to said limit value includes the step of controlling said mechanism to change said phase to said limit value after said internal combustion engine is stopped if said predetermined condition is satisfied; and   the step of controlling said mechanism to change said phase from said limit value includes the step of controlling said mechanism to change said phase from said limit value after said internal combustion engine is stopped if said predetermined condition is satisfied.   
   
   
       12 . The method of controlling an internal combustion engine according to  claim 10 , wherein:
 said mechanism includes a motor electrically operated and having an output shaft rotating to change said phase in which said valve opens/closes;   the step of detecting said amount includes the step of detecting a number of rotations of said output shaft of said motor accumulated; and   the step of detecting said phase includes the step of detecting said phase as based on said number of rotations of said output shaft of said motor accumulated.   
   
   
       13 . A control device for an internal combustion engine provided with a mechanism changing a phase in which at least one valve of an intake valve and an exhaust valve opens/closes, comprising:
 control means for controlling said mechanism to change said phase when a predetermined condition associated with stopping said internal combustion engine is satisfied;   first detection means for detecting an amount by which said mechanism is operated when said mechanism is controlled by said control means; and   second detection means for detecting said phase based on said amount, wherein said control means includes means for controlling said mechanism to change said phase detected by said second detection means to attain a predetermined value.   
   
   
       14 . The control device for an internal combustion engine according to  claim 13 , wherein said control means includes means for controlling said mechanism to change said phase after said internal combustion engine is stopped if said predetermined condition is satisfied. 
   
   
       15 . The control device for an internal combustion engine according to  claim 13 , wherein:
 said mechanism includes a motor electrically operated and having an output shaft rotating to change said phase in which said valve opens/closes;   said first detection means includes means for detecting a number of rotations of said output shaft of said motor accumulated; and   said second detection means includes means for detecting said phase as based on said number of rotations of said output shaft of said motor accumulated.   
   
   
       16 . A control device for an internal combustion engine provided with a mechanism changing a phase in which at least one valve of an intake valve and an exhaust valve opens/closes, comprising:
 first control means for controlling said mechanism to change said phase to attain a limit value when a predetermined condition associated with stopping said internal combustion engine is satisfied, said limit value being one of values of maximally retarded and advanced angles, respectively;   second control means for controlling said mechanism to change said phase from said limit value if said predetermined condition is satisfied;   first detection means for detecting an amount by which said mechanism is operated when said mechanism is controlled by said second control means; and   second detection means for detecting said phase based on said amount, wherein said second control means includes means for controlling said mechanism to change said phase detected by said second detection means to attain a predetermined value.   
   
   
       17 . The control device for an internal combustion engine according to  claim 16 , wherein:
 said first control means includes means for controlling said mechanism to change said phase to said limit value after said internal combustion engine is stopped if said predetermined condition is satisfied; and   said second control means includes means for controlling said mechanism to change said phase from said limit value after said internal combustion engine is stopped if said predetermined condition is satisfied.   
   
   
       18 . The control device for an internal combustion engine according to  claim 16 , wherein:
 said mechanism includes a motor electrically operated and having an output shaft rotating to change said phase in which said valve opens/closes;   said first detection means includes means for detecting a number of rotations of said output shaft of said motor accumulated; and   said second detection means includes means for detecting said phase as based on said number of rotations of said output shaft of said motor accumulated.