Patent US2780968A successfully refreshed from Google Patents.
EP0243871B1
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EP
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Fuel injection system
Assignee: Denso Corp
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Filing: 1987-04-23
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Granted: 1993-07-07
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Expires: 2007-04-23
Abstract
No abstract record available.
Inventors
- 👤 Masahiko Miyaki
- 👤 Takashi Iwanaga
- 👤 Hideya Fujisawa
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 13:02
CPC Classifications
F; F02; F02M; F02M63/00; F02M63/02; F02M63/0225; F02D; F02D41/00; F02D41/30; F02D41/38; F02D41/3809; F02D41/3827; F02D41/3836; F02D41/3845; F02M59/00; F02M59/20; F02M59/36; F02M59/366; F02M59/44; F02M59/46; F02M59/466; F02M59/48; F02M63/0003; F02M63/0007; F02B; F02B3/00; F02B3/06; F02D2200/00; F02D2200/02; F02D2200/06; F02D2200/0602; F02D2250/00; F02D2250/31; F02M2200/00; F02M2200/40
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
278 words
A fuel injection system for an internal combustion engine comprising low pressure fuel supply means (8,9,49) for supplying low pressure fuel; high pressure fuel pump means (7,20) having a pump chamber (40,41,42) communicated with said low pressure fuel supply means and a plunger (31,32,33) reciprocable within said pump chamber for introducing fuel from said low pressure fuel supply means during a movement in a predetermined direction and pressurizing the introduced fuel during movement in the opposite direction; common rail fuel storage means (4) for storing therein the pressurized fuel delivered from said high pressure pump; fuel injection means (2,3) including a fuel injector for injecting into said internal combustion engine the pressurized fuel stored in said common rail fuel storage means when activated; spill passage means (58,59,60) communicating said pump chamber to said low pressure fuel supply means; electrically-controlled spill valve means (46,47,48) positioned in said spill passage means for closing and opening said spill passage means in response to a spill control signal applied thereto; electric control means (11,12,13) for producing the spill control signal in accordance with operating conditions of said internal combustion engine; and electrically controlled valve (3) for activating said fuel injector in response to an injection control signal applied thereto, and wherein said electric control means produces said injection control signal in accordance with the operating conditions of said engine, characterized in that the electric control means (11, 12, 13) closes the spill valve means (46, 47, 48) before the plunger (31, 32, 33) starts pressurizing and controls the amount of injected fuel every time, so that the fuel pressure in the common rail fuel storage means is maintained on a certain level.
Claim 2
Dependent Claim
278 words
A fuel injection system for an internal combustion engine comprising low pressure fuel supply means (8,9,49) for supplying low pressure fuel; high pressure fuel pump means (7,20) having a pump chamber (40,41,42) communicated with said low pressure fuel supply means and a plunger (31,32,33) reciprocable within said pump chamber for introducing fuel from said low pressure fuel supply means during a movement in a predetermined direction and pressurizing the introduced fuel during movement in the opposite direction; common rail fuel storage means (4) for storing therein the pressurized fuel delivered from said high pressure pump; fuel injection means (2,3) including a fuel injector for injecting into said internal combustion engine the pressurized fuel stored in said common rail fuel storage means when activated; spill passage means (58,59,60) communicating said pump chamber to said low pressure fuel supply means; electrically-controlled spill valve means (46,47,48) positioned in said spill passage means for closing and opening said spill passage means in response to a spill control signal applied thereto; electric control means (11,12,13) for producing the spill control signal in accordance with operating conditions of said internal combustion engine; and electrically controlled valve (3) for activating said fuel injector in response to an injection control signal applied thereto, and wherein said electric control means produces said injection control signal in accordance with the operating conditions of said engine, characterized in that the electric control means (11, 12, 13) closes the spill valve means (46, 47, 48) before the plunger (31, 32, 33) starts pressurizing and controls the amount of injected fuel every time, so that the fuel pressure in the common rail fuel storage means is maintained on a certain level.
Claim 3
Dependent Claim
83 words
A fuel injection system according to claim 1, wherein said high pressure pump means (8, 9, 49) further has a feed hole (37, 38, 39) communicating with said low pressure fuel supply means and said plunger (31, 32, 33) is provided with a further spill passage (55, 56, 57) which communicates said pump chamber (40, 41, 42) to said feed hole (37, 38, 39) when said plunger (31, 32, 33) is moved closely to the end of the movement in said opposite direction.
Claim 4
Dependent Claim
66 words
A fuel injection system according to claim 2, wherein said high pressure pump means (8, 9, 49) has a cam (22, 23, 24) engaging said plunger (31, 32, 33) and driven by an output shaft (21) of said diesel engine, said cam having two crests so that said plunger (31, 32, 33) is moved twice in said opposite direction for each rotation of said output shaft.
Claim 5
Dependent Claim
78 words
A fuel injection system according to claim 3, wherein a shaft (21) for driving at least one (22, 23, 24) cam rotates at a speed half of the engine speed, the profile of each cam is so shaped that it has a plurality of crests for driving the plungers (31, 32, 33) and the number of the plungers (31, 32, 33) is the number of the engine cylinders divided by the number of the crests on each cam.
Claim 6
Dependent Claim
68 words
A fuel injection system according to claim 3, wherein a shaft (21) for driving at least one cam (22, 23, 24) rotates at the same speed as the engine speed, the profile of each cam is so shaped that it has one crest for driving the plungers (31, 32, 33), and the number of the plungers (31, 32, 33) is half of the number of the engine cylinders.
Claim 7
Dependent Claim
80 words
A fuel injeciton system according to claims 4 or 5, further including a rotary disk (61) mounted on the shaft (21), an electromagnetic pickup (62) mounted corresponding to the disk, and protrusions formed on the disk so as to correspond to the number of the engine cylinders, and wherein the control means opens and closes the spill valve means (46) in accordance with an output signal from a pickup that indicates the angular positions of the at least one cams.
Claim 8
Dependent Claim
84 words
A fuel injection system according to claim 6, further including a cylinder discriminator comprising a rotary disk (61) for producing one signal per revolution of the shaft driving the at least one cam and an electromagnetic pickup (62), in addition to the rotary disk having the same number of protrusions as the number of the engine cylinders, and wherein the control means closes successively the spill valves means (46) which enter into the delivery stroke, according to the output signal from the cylinder discriminator.
Claim 9
Dependent Claim
93 words
The fuel injection system according to claim 1, wherein a pressure sensor (14) is disposed in the common rail fuel storage means (4) to detect the pressure inside the common rail fuel storage means (4), and wherein the control means controls the periods (T) of closure of the spill valve means (46) in such a way that the value (P c ) indicated by the output signal from the pressure sensor becomes equal to a value (P o ) which has been previously set according to the engine load and the engine speed.
References Cited (Backward Citations)
No citation records indexed.
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