Timing and speed sensor for fuel injection pump

Claim 1

Apparatus comprising: a first rotating member; a second rotating member; coupling means for driving said second rotating member in syntony with and at variable rotational angles with respect to said first rotating member; first sensor means for producing reference pulses indicative of the times of occurrence of only one specific reference rotational position of said first rotating member; wheel means synchronously driven by said second rotating member and having a plurality of tooth members evenly spaced about it; second sensor means disposed adjacent said wheel means for producing a pulse for each occurrence of a juxtaposition one of said tooth members with said second sensor means; means responsive to said pulse from said second sensor means for providing a speed signal indicative of the rotational speed of said second rotating member, in response to the frequency or time interval between said pulses; means for producing a time-difference signal indicative of the timer interval between each pulse from said first sensor means and a next adjacent pulse from said second sensor means; and means responsive to said speed signal and to said time-difference signal for producing a signal which is a function of the product of said rotational speed times said time interval, and indicative of the angle between said first and second rotating members.