US5908022A — Fuel-injection control device for a diesel engine

Claim 1

Independent Claim 107 words

A fuel-injection control device for a diesel engine having a common-rail-type fuel-injection pump comprising: an EGR control means for adjusting an EGR ratio, between zero and a maximum EGR ratio, according to an engine load; a means for controlling fuel-injection pressure based on the EGR ratio and the engine load, so that a previously calculated amount of fuel is injected at the pressure determined by the fuel-injection pressure control means thereby reducing an amount of smoke and NO x generated through combustion of the fuel, wherein said means for controlling fuel-injection pressure includes a correcting means for correcting said fuel-injection pressure in response to said EGR ratio.

Claim 2

Dependent Claim 107 words

A fuel-injection control device for a diesel engine having a common-rail-type fuel-injection pump comprising: an EGR control means for adjusting an EGR ratio, between zero and a maximum EGR ratio, according to an engine load; a means for controlling fuel-injection pressure based on the EGR ratio and the engine load, so that a previously calculated amount of fuel is injected at the pressure determined by the fuel-injection pressure control means thereby reducing an amount of smoke and NO x generated through combustion of the fuel, wherein said means for controlling fuel-injection pressure includes a correcting means for correcting said fuel-injection pressure in response to said EGR ratio.

Claim 3

Dependent Claim 28 words

A fuel-injection control device as set forth in claim 1, wherein said means for controlling fuel-injection pressure controls to increase said fuel-injection pressure as the engine load increases.

Claim 4

Dependent Claim 39 words

A fuel-injection control device as set forth in claim 1, wherein said EGR control means provides some actual value of said EGR ratio in the lower-to-middle range of engine load and zero in the higher range of engine load.

Claim 5

Dependent Claim 45 words

A fuel-injection control device as set forth in claim 1, wherein said correcting means adjusts said fuel-injection pressure to a higher level when said EGR control is enabled so as to suppress the amount of emitted smoke to below the upper limit of some emission.

Claim 6

Dependent Claim 39 words

A fuel-injection control device as set forth in claim 1, wherein said correcting means adjusts said fuel-injection pressure to a higher level when said EGR control is enabled and to a lower level when said EGR control is disabled.

Claim 7

Dependent Claim 56 words

A fuel-injection control device as set forth in claim 5, wherein said correcting means selects a higher pressure control map for adjusting said fuel-injection pressure to a higher level when said EGR control is enabled and a lower pressure control map for adjusting said fuel-injection pressure to a lower level when said EGR control is disabled.

Claim 8

Dependent Claim 52 words

A fuel-injection control device as set forth in claim 5, wherein said correcting means includes a calculating means to calculate a correction value for adjusting said fuel-injection pressure to either said higher level or said lower level and to add said correction value to a pressure control map for the other level.

Claim 9

Dependent Claim 26 words

A fuel-injection control device as set forth in claim 7, wherein said calculating means contains a correcting equation determined as a function of engine operation factors.

Claim 10

Dependent Claim 24 words

A fuel-injection control device as set forth in claim 5, wherein the difference between said higher level and said lower level is 10-30 PMa.

Claim 11

Dependent Claim 88 words

In a fuel-injection control device for a diesel engine using a common-rail-type fuel-injection pump and an EGR control, said fuel-injection control device comprising: a detecting means for detecting a warming-up state of said engine, and a control means for controlling the fuel-injection pressure in said common-rail-type fuel-injection pump and the operation of said EGR control according to said detected warming-up state of said engine, in which said fuel-injection pressure is lessened to a lower level and said EGR control is disabled at least when said engine is cold.

Claim 12

Dependent Claim 88 words

In a fuel-injection control device for a diesel engine using a common-rail-type fuel-injection pump and an EGR control, said fuel-injection control device comprising: a detecting means for detecting a warming-up state of said engine, and a control means for controlling the fuel-injection pressure in said common-rail-type fuel-injection pump and the operation of said EGR control according to said detected warming-up state of said engine, in which said fuel-injection pressure is lessened to a lower level and said EGR control is disabled at least when said engine is cold.

Claim 13

Dependent Claim 26 words

A fuel-injection control device as set forth in claim 10, wherein said detecting means uses cooling water temperature for detecting a warming-up state of said engine.

Claim 14

Dependent Claim 56 words

A fuel-injection control device as set forth in claim 10, wherein said control means includes a first control means for disabling said EGR control as well as adjusting said fuel-injection pressure to a lower level and a second control means for enabling said EGR control as well as adjusting said fuel-injection pressure to a higher level.

Claim 15

Dependent Claim 30 words

A fuel-injection control device as set forth in claim 12, wherein at least one of said first and second control means contains a control map for adjusting said fuel-injection pressure.

Claim 16

Dependent Claim 120 words

A fuel-injection control device for a diesel engine having a common-rail-type fuel-injection pump comprising: fuel-injection amount calculation means for determining a fuel injection amount based on an engine load; an EGR control means for adjusting an EGR ratio according to engine load between zero and a maximum EGR ratio; a controller for controlling a pressure at which fuel is to be injected based on the current EGR ratio and the engine load; and fuel-injection timing means for determining, based on the fuel-injection amount and the fuel-injection pressure, a duration for which fuel is to be injected, so that, for a given fuel-injection amount, a change in the EGR ratio results in a change in the fuel injection pressure and duration.

Claim 17

Dependent Claim 120 words

A fuel-injection control device for a diesel engine having a common-rail-type fuel-injection pump comprising: fuel-injection amount calculation means for determining a fuel injection amount based on an engine load; an EGR control means for adjusting an EGR ratio according to engine load between zero and a maximum EGR ratio; a controller for controlling a pressure at which fuel is to be injected based on the current EGR ratio and the engine load; and fuel-injection timing means for determining, based on the fuel-injection amount and the fuel-injection pressure, a duration for which fuel is to be injected, so that, for a given fuel-injection amount, a change in the EGR ratio results in a change in the fuel injection pressure and duration.

Claim 18

Dependent Claim 156 words

A diesel engine comprising: a common-rail fuel-injection pump, for injecting fuel directly into at least one cylinder of the engine; an intake passage for supplying air to the at least one cylinder; an exhaust gas recirculation passage for recirculating exhaust gas from the engine back to the intake passage; an EGR controller for adjusting an EGR ratio, according to an engine load, between zero and a maximum EGR ratio; a fuel quantity controller for controlling a quantity of fuel to be injected to the at least one cylinder based on engine operating conditions; a pressure controller for controlling the pressure at which the quantity of fuel is injected based on the engine load and a diffusion characteristic of the injected fuel and the air from the intake passage to reduce an amount of smoke and NO x generated through combustion of the fuel, wherein the pressure controller corrects the fuel-injection pressure based on the EGR ratio.

Claim 19

Dependent Claim 156 words

A diesel engine comprising: a common-rail fuel-injection pump, for injecting fuel directly into at least one cylinder of the engine; an intake passage for supplying air to the at least one cylinder; an exhaust gas recirculation passage for recirculating exhaust gas from the engine back to the intake passage; an EGR controller for adjusting an EGR ratio, according to an engine load, between zero and a maximum EGR ratio; a fuel quantity controller for controlling a quantity of fuel to be injected to the at least one cylinder based on engine operating conditions; a pressure controller for controlling the pressure at which the quantity of fuel is injected based on the engine load and a diffusion characteristic of the injected fuel and the air from the intake passage to reduce an amount of smoke and NO x generated through combustion of the fuel, wherein the pressure controller corrects the fuel-injection pressure based on the EGR ratio.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	2002-05-31	2002-11-30	2003-06-01	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	2006-05-31	2006-11-30	2007-06-01	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2010-05-31	2010-11-30	2011-06-01	$7700.00	Window Closed / Lapsed

Fuel-injection control device for a diesel engine

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