Patent ID: 7184876

Claim:
Device ( 1 ) for determining the position of an internal combustion engine that comprises a rotary element, whereby said device comprises: A sensor ( 2 ) that comprises a rotary part ( 8 ) and a fixed part ( 6 ), whereby said rotary part ( 8 ) is linked to the rotary part and comprises a number of essentially identical reference points ( 26 ) that are offset angularly by one increment, whereby said fixed part ( 6 ) comprises: First means ( 16 , 18 , 22 , 30 ) for generating a first signal ( 32 ) based on the relative position of reference points ( 26 ) relative to the fixed part ( 6 ), Second means ( 16 , 20 ) for generating a second signal ( 34 ) based on the relative position of the reference points ( 26 ) relative to the fixed part ( 6 ), whereby said first signal ( 32 ) and said second signal ( 34 ) are similar but phase-shifted, Means of analysis ( 10 ) connected to the first means ( 16 , 18 , 22 , 30 ) and to the second means ( 16 , 20 ), whereby said means of analysis ( 10 ) comprise third means ( 46 ) for detecting at least one characteristic event ( 12 , 14 ) on the first signal and fourth means ( 48 ) for generating a third signal ( 36 ) of binary type that takes on a first value ( 36 MAX ) or a second value ( 36 min ), whereby said fourth means ( 18 ) generate an alternation of the third signal ( 36 ) between the first value ( 36 MAX ) and the second value ( 36 min ) after detection of at least one of characteristic events ( 12 , 14 ) on the first signal ( 32 ), Engine control means ( 4 ) connected to the means of analysis of sensor ( 10 ), whereby said engine control means ( 4 ) comprise: A counter ( 56 ) that is intended to represent the position of the rotary element, Fifth means ( 50 ) for detecting the alternations of the third signal ( 36 ) between the first value ( 36 MAX ) and the second value ( 36 min ) and to modify the counter ( 56 ) based on said alternations, Sixth means ( 52 ) for generating actions on engine elements based on the value of counter ( 56 ), characterized in that means of analysis ( 10 ) also comprise: Means of comparison ( 42 ) to compare the value of the second signal ( 34 ) to a reference value, when a characteristic event ( 12 , 14 ) is detected on the first signal ( 32 ), Control means ( 44 ) for controlling the fourth means ( 48 ) for alternating the third signal ( 36 ) between the first value ( 36 MAX ) and the second value ( 36 min ) only when a characteristic event ( 12 , 14 ) is detected on the first signal ( 32 ) and when the result of the comparison ( 58 ) is positive.