Multi-mode digital control apparatus

Claim 2

Apparatus for testing plural injector fuel equipment driven through a rotating shaft, comprising: a motor; a hydrostatic transmission driven by the motor and having an output shaft adapted to be connected to the rotating shaft of the fuel injection equipment, said hydrostatic transmission including speed adjusting means operative to adjust the speed of the output shaft in accordance with a speed error signal; a plurality of receptacles for accumulating fuel discharged by each of a plurality of the fuel injectors; valve means for each of said receptacles for controlling the flow of fluid to the associated receptacle; a multi-mode control means comprising pulse generating means operative to generate a predetermined number of pulses per revolution of the shaft of the fuel injection equipment; counting means; speed mode control means including means for applying the pulses generated by the pulse generator to the counting means for preselected intervals, means for generating a speed error signal as a function of the difference between the number of pulses applied to the counting means in the preselected interval and a preselected count and means for resetting the counting means prior to each interval; and count mode control means including means for applying the pulses generated by the pulse generator to the counting means continuously until a preset count is accumulated, and means for opening the valve means to permit fuel from each of the fuel injectors to flow into the associated receptacle at the beginning of the count and for shutting off the valve means to discontinue the flow to the receptacles when the preset count is reached.

Claim 3

The apparatus of claim 2 including digital display means for displaying a digital count stored therein, and wherein the multi-mode control means includes tachometer mode control means comprising means for applying the pulses generated by the pulse generator to the counting means for predetermined intervals, means for applying the accumulated count to the display means at the end of each interval and means for resetting the counting means prior to each interval.

Claim 4

The apparatus of claim 2 wherein said count mode control means includes means for continuously applying the count accumulated in the counting means to the digital means.

Claim 5

The apparatus of claim 3 wherein the count mode control means also includes means for dividing down the pulses generated by the pulse generating means by the number of pulses generated by the pulse generating means per revolution of the pump shaft and means for applying the resultant pulses to the digital counting means whereby the digital display means will directly display the number of revolutions turned.

Claim 6

The apparatus of claim 2 including means to activate the tachometer mode control means and the speed mode control means simultaneously and wherein said preselected interval and said predetermined interval are the same interval.

Claim 7

The apparatus of claim 1 including means responsive to the accumulation of said preset count under control of the count mode control means to transfer control to said speed mode control means.

Claim 8

Apparatus for controlling a hydrostatic transmission having means responsive to a speed error signal for setting the speed of rotation of the output shaft thereof, comprising: pulse generating means operative to generate a predetermined number of pulses for each revolution of the output shaft of the hydrostatic transmission; digital counting means; and speed control means including means for applying the pulses generated by the pulse generating means to the digital counting means for preselected intervals, means responsive to the difference between the count accumulated in the counting means during the preselected intervals and a preselected count and operative to generate a pulsed speed error signal when said difference is less than a first count and operative to generate a continuous speed error signal when said difference exceeds the first count, and reset means for resetting the counting means at the end of each interval.

Claim 9

Apparatus for controlling a hydrostatic transmission having means responsive to a speed error signal for setting the speed of rotation of the output shaft thereof, comprising: pulse generating means operative to generate a predetermined number of pulses for each revolution of the output shaft of the hydrostatic transmission; digital counting means; and speed control means including means for applying the pulses generated by the pulse generating means to the digital counting means for preselected intervals, means responsive to the difference between the count accumulated in the counting means during the preselected intervals and a preselected count and operative to generate a pulsed speed error signal when said difference is less than a first count and operative to generate a continuous speed error signal when said difference exceeds the first count, and reset means for resetting the counting means at the end of each interval.

Claim 10

The apparatus of claim 7 wherein said reset means includes means for loading the preselected count into the counting means and for setting the counting means to count down at the end of each interval, wherein said means for applying the pulses generated by the pulse generating means to the counting means includes means for causing the counting means to reverse counting direction and count in the up direction when the count reaches zero during said preselected interval, and wherein said means responsive to the difference between the accumulated count and the preselected count includes means operative to generate a continuous speed error signal when the accumulated count remaining at the end of the preselected interval exceeds said first count, means operative to generate a speed error signal in the form of a pulse shorter in duration than the preselected interval when the accumulated count remaining is equal to or less than said first count but more than a second count, means operative to generate no speed error signal when the remaining count is equal to or less than the second count, and means operative for setting the polarity of the speed error signal to produce an increase in the speed of the hydrostatic transmission when the counting means does not reach zero during the preselected interval and to produce a decrease in speed when the counting means does reach zero.

Claim 11

The apparatus of claim 7 wherein said reset means includes means for loading the preselected count into the counting means and for setting the counting means to count down at the end of each preselected interval, wherein said means for applying the pulses generated by the pulse generating means to the counting means includes means for causing the counting means to reverse counting direction and count in the up direction when the count reaches zero during said preselected interval, and wherein said means responsive to the difference between the accumulated count and the preselected count includes additional counting means, means for resetting the additional counting means to zero at the end of each preselected interval, means responsive each time the count in the counting means reaches said first count while counting in either direction and each time the count in the counting means reaching a second count which is less than said first count while counting in either direction for applying a pulse to the additional counting means, and means responsvie to the count accumulated in the additional counting means during each interval for generating a continuous decrease speed error signal when a count of zero is accumulated in the additional counting means, means for generating a decrease speed error signal in the form of a pulse signal having a duration shorter than the preselected interval when a count of 1 is accumulated in the additional counting means, means for generating no speed error signal when a count of 2 is accumulated in the additional counting means, means for generating an increase speed error signal in the form of a pulse signal having a duration shorter than said preselected interval when a count of 3 is accumulated in the additional counting means and means for generating a continuous decrease speed error signal when a count of 4 is accumulated in the additional counting means.

Claim 12

Apparatus for providing multi-mode control of rotating equipment, comprising: a pulse generator oPerative to generate a predetermined number of pulses for each revolution of the rotating equipment; digital counting means; digital display means operative to generate a digital readout representative of a digital count stored therein; speed control means operative to control the speed of the rotating equipment in response to a speed error signal; count mode control means including means to continuously apply the pulses generated by the pulse generator to the counting means and means to continuously apply the accumulated count in the counting means to the digital display means; tachometer mode control means including means to apply the pulses generated by the pulse generator to the counting means for predetermined intervals, means for applying the accumulated count to the display means at the end of each interval, and means for resetting the counting means prior to each interval; and speed mode control means including means for applying the pulses generated by the pulse generator to the counting means for preselected intervals, means for generating a speed error signal as a function of the difference between the number of pulses applied to the counting means in the preselected interval and a preselected count and means for resetting the counting means prior to each interval.

Claim 13

Apparatus for providing multi-mode control of rotating equipment, comprising: a pulse generator oPerative to generate a predetermined number of pulses for each revolution of the rotating equipment; digital counting means; digital display means operative to generate a digital readout representative of a digital count stored therein; speed control means operative to control the speed of the rotating equipment in response to a speed error signal; count mode control means including means to continuously apply the pulses generated by the pulse generator to the counting means and means to continuously apply the accumulated count in the counting means to the digital display means; tachometer mode control means including means to apply the pulses generated by the pulse generator to the counting means for predetermined intervals, means for applying the accumulated count to the display means at the end of each interval, and means for resetting the counting means prior to each interval; and speed mode control means including means for applying the pulses generated by the pulse generator to the counting means for preselected intervals, means for generating a speed error signal as a function of the difference between the number of pulses applied to the counting means in the preselected interval and a preselected count and means for resetting the counting means prior to each interval.

Claim 14

The apparatus of claim 10 wherein the digital counting means includes a first digital counter and a second digital counter, and wherein the tachometer mode control means includes means for gating pulses to the first counter and the speed mode control means includes means for gating pulses to the second counter whereby both the tachometer mode and the speed mode can be selected simultaneously.

Claim 15

The apparatus of claim 10 wherein the reset means in the speed mode control means includes means for resetting the counting means to the preselected count prior to each interval, wherein the means for applying pulses to the counting means includes means for causing the counting means to count down from said preselected count in response to the applied pulses and wherein the speed error signal generating means includes means for generating an increase speed error signal when the count in the counting means does not reach zero by the end of the preselected interval and means for generating a decrease speed error signal when the count in the counting means does reach zero before the end of the preselected interval.

Claim 16

The apparatus of claim 12 wherein the means within the speed mode control means for applying pulses to the counting means includes means for causing the counting means to count the remaining pulses applied during an interval in the up direction when the count reaches zero before the end of an interval and wherein the speed error signal generating means includes means for generating a speed error signal having a first value when the count remaining at the end of the interval is less than a predetermined count and means for generating a speed error signal having a second value when the count remaining is equal to or more than the predetermined count.

Claim 17

The apparatus of claim 13 wherein the means for generating a speed error signal having a first value includes means for generating a signal having a duration which is less than the preselected interval and wherein the means for generating a speed error signal having a second value includes means for generating a signal having a duration at least as long as said predetermined interval.

Claim 18

The apparatus of claim 10 wherein the count mode control means includes means for dividing down the pulses generated by the pulse generating means by the number of pulses generated by the pulse generating means per revolution of the rotating equipment, and means for applying the resultant pulses to the digital counting means, whereby the digital display means will directly display the number of revolutions turned.

Claim 19

The apparatus of claim 10 wherein the predetermined interval during which pulses are applied to the countiNg means by the tachometer mode control means is equal to the unit of time selected for measuring the rate of rotation of the rotating apparatus divided by the predetermined number of pulses generated per revolution by the pulse generating means, whereby the count accumulated in the counting means at the end of the interval will be equal to the speed of rotation in the selected unit of measure and the digital display device will present a direct reading of the speed of rotation.