Injection type fuel feeder

Claim 2

A fuel feed control system for controlling the supPly of fuel fed to an engine in accordance with at least one engine operating condition, comprising condition detecting means for generating an electrical condition signal corresponding to the level of engine manifold pressure, timing means for periodically generating a timing signal having a linearly increasing amplitude with time, and level detecting means responsive to the sum of said condition and timing signals for generating a fuel control signal whose duration equals the time required for the sum of said condition and timing signals to reach a prescribed value, said timing means including control means responsive to one given value of engine manifold pressure forming a critical point between the economical output region and the high output region of the engine operating characteristic for adjusting the rate of change of said timing signal from a first value to a second value.

Claim 3

A fuel feed control system as defined in claim 1, wherein said level detecting means includes summing means for summing said condition signal and said timing signal and switching means responsive to said summed signal value for providing said fuel control signal for all levels of said summed signal value below a given limit.

Claim 4

A fuel feed control system as defined in claim 2, wherein said condition detecting means generates a plurality of condition signals relating to different engine conditions and said summing means sums all of said condition signals with said timing signal.

Claim 5

A fuel feed control system as defined in claim 1, wherein said control means in said timing means includes delay means for gradually adjusting the rate of change of said timing signal upon detection of said given value of engine manifold pressure.

Claim 6

A fuel feed control system as defined in claim 4, wherein said timing means includes a pulse generator and a timing signal generating circuit responsive to the output of said pulse generator for generating a sawtooth wave timing signal.

Claim 7

A fuel feed control system as defined in claim 5, wherein said timing signal generating circuit includes a timing capacitor connected to a constant current source and means responsive to the output of said pulse generator for periodically discharging said timing capacitor, said control means including means responsive to said change in engine manifold pressure for changing the level of the current generated by said constant current source.

Claim 8

A fuel feed control system as defined in claim 6, wherein said level detecting means includes summing means for summing said condition signal and said timing signal and switching means responsive to said summed signal value for providing said fuel control signal for all levels of said summed signal value below a given limit.

Claim 9

A fuel feed control system as defined in claim 7, wherein said condition detecting means generates a plurality of condition signals relating to different engine conditions and said summary means sums all of said condition signals with said timing signal.

Claim 10

A fuel feed control system as defined in claim 1, wherein said level detecting means comprises a plurality of resistances connecting a plurality of input terminals to a common summing point, an Esaki diode connected between said summing point and ground, and a transistor having its base connected to said summing point, its collector connected through a resistance to a power source and its emitter connected to ground, said timing means being connected to apply said timing signal to one of said input terminals and said condition detecting means applying a plurality of condition signals relating to different engine conditions to the remaining input terminals.

Claim 11

A fuel feed control system as defined in claim 9, wherein said timing means comprises a timing capacitor connected in series with a transistor constant current source, a pulse generator, a transistor switch connected to said pulse generator and said timing capacitor for periodically discharging said timing capacitor, and meAns for changing the level of said constant current source including a delay capacitor for effecting a delay in the change of current level of said constant current source.

Claim 12

A fuel feed control system for controlling the supply of fuel fed to an engine in accordance with at least one engine operating condition, comprising condition detecting means for generating an electrical condition signal corresponding to said engine operating condition, said condition signal corresponding to a condition selected from the group consisting of manifold pressure, engine temperature and engine speed, timing means for periodically generating a timing signal having a linearly increasing amplitude with time, said timing means including a pulse generator and a timing signal generating circuit responsive to the output of said pulse generator for generating a sawtooth wave timing signal, and level detecting means responsive to the sum of said condition and timing signals for generating a fuel control signal whose duration equals the time required for the sum of said condition and timing signals to reach a prescribed value, said timing means further including control means responsive to one given value of engine manifold pressure forming a critical point between the economical output region and the high output region of the engine operating characteristic for adjusting the rate of change of said timing signal from a first value for said economical output region to a second value for said high output region, said control means including delay means for gradually transferring the rate of said timing signal upon detection of said critical point from said first value for said economical output region to said second value for said high output region.

Claim 13

A fuel feed control system for controlling the supply of fuel fed to an engine in accordance with at least one engine operating condition, comprising condition detecting means for generating an electrical condition signal corresponding to said engine operating condition, said condition signal corresponding to a condition selected from the group consisting of manifold pressure, engine temperature and engine speed, timing means for periodically generating a timing signal having a linearly increasing amplitude with time, said timing means including a pulse generator and a timing signal generating circuit responsive to the output of said pulse generator for generating a sawtooth wave timing signal, and level detecting means responsive to the sum of said condition and timing signals for generating a fuel control signal whose duration equals the time required for the sum of said condition and timing signals to reach a prescribed value, said timing means further including control means responsive to one given value of engine manifold pressure forming a critical point between the economical output region and the high output region of the engine operating characteristic for adjusting the rate of change of said timing signal from a first value for said economical output region to a second value for said high output region, said control means including delay means for gradually transferring the rate of said timing signal upon detection of said critical point from said first value for said economical output region to said second value for said high output region.