Rotational position detector for controlling an internal combustion engine

Claim 1

A rotational position detector for controlling an internal combustion engine comprising: a rotary body rotatable in synchronism with internal combustion engine operation; a plurality of detectable portions disposed on said rotary body; pulse generating means operatively positioned adjacent to said rotary body for generating a pulse output each time one of said detectable portions on said rotary body passes said pulse generating means; measuring means for measuring time intervals between respective pulses, a preceding pulse and a present pulse, and developing an output; an increase/decrease discriminator adapted to compare previous and present values of the output of said measuring means to check for an increase or decrease therein as compared with a predetermined value and developing an output; and memory means for storing the output of said increase/decrease discriminator for a predetermined period in an increase/decrease pattern and developing an output for controlling the operation of said internal combustion engine; wherein the increase/decrease discriminating pattern comprises an increase/decrease time length discriminator and pattern checking means for checking malfunction of the pattern showing increase/decrease sequence of time distance between each inputted pulse.

Claim 8

A device for detecting a reference position of a rotary body comprising: a plural number of detectable portions located around the circumference of a rotary body at uniform intervals except for at least one nonuniformly spaced detectable portion; a sensor located in a position close to said rotary body for detection of said detectable portions and developing output signals; and a control circuit responsive to said output signals of said sensor and adapted to determine a time ratio of R (=T si-1 /T si ) and a time length L (=T si-1 -T si ) from a time interval T si between two output signals and a previous time interval T si-1 to determine as said reference position a position of a larger rotational angle in terms of the time ratio R (=T si-1 /T si ) and the time length L (=T si-1 -T si ), said control circuit counting each one of said detectable portions and discriminating a true reference position when a count corresponding to said reference position conforms with the count corresponding to a recurred reference position, and producing an increase/decrease output signal on the basis of the discriminating true reference position; wherein the increase/decrease output signal pattern comprises an increase/decrease time length discriminator and pattern checking means for checking malfunction of the pattern showing increase/decrease sequence of time distance between each inputted signal.

Claim 9

A device for detecting a reference position of a rotary body comprising: a plural number of detectable portions located around the circumference of a rotary body at uniform intervals except for at least one nonuniformly spaced detectable portion; a sensor located in a position close to said rotary body for detection of said detectable portions and developing output signals; and a control circuit responsive to said output signals of said sensor and adapted to determine a time ratio of R (=T si-1 /T si ) and a time length L (=T si-1 -T si ) from a time interval T si between two output signals and a previous time interval T si-1 to determine as said reference position a position of a larger rotational angle in terms of the time ratio R (=T si-1 /T si ) and the time length L (=T si-1 -T si ), said control circuit counting each one of said detectable portions and discriminating a true reference position when a count corresponding to said reference position conforms with the count corresponding to a recurred reference position, and producing an increase/decrease output signal on the basis of the discriminating true reference position; wherein the increase/decrease output signal pattern comprises an increase/decrease time length discriminator and pattern checking means for checking malfunction of the pattern showing increase/decrease sequence of time distance between each inputted signal.