Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M37/00—Apparatus or systems for feeding liquid fuel from storage containers to carburettors or fuel-injection apparatus; Arrangements for purifying liquid fuel specially adapted for, or arranged on, internal-combustion engines
  • F02M37/0047—Layout or arrangement of systems for feeding fuel
  • F02M37/0052—Details on the fuel return circuit; Arrangement of pressure regulators
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M37/00—Apparatus or systems for feeding liquid fuel from storage containers to carburettors or fuel-injection apparatus; Arrangements for purifying liquid fuel specially adapted for, or arranged on, internal-combustion engines
  • F02M37/02—Feeding by means of suction apparatus, e.g. by air flow through carburettors
  • F02M37/025—Feeding by means of a liquid fuel-driven jet pump
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M37/00—Apparatus or systems for feeding liquid fuel from storage containers to carburettors or fuel-injection apparatus; Arrangements for purifying liquid fuel specially adapted for, or arranged on, internal-combustion engines
  • F02M37/04—Feeding by means of driven pumps
  • F02M37/08—Feeding by means of driven pumps electrically driven
  • F02M37/10—Feeding by means of driven pumps electrically driven submerged in fuel, e.g. in reservoir
  • F02M37/106—Feeding by means of driven pumps electrically driven submerged in fuel, e.g. in reservoir the pump being installed in a sub-tank

Definitions

• the present invention relates to a fuel system for an internal combustion engine, in which a fuel pump supplies fuel to the engine via a forward line and is arranged in a fuel chamber which is accommodated in a fuel tank and is designed with side wall and upper wall, to which fuel chamber fuel can be transferred from the fuel tank by means of an ejector which is driven by a fuel flow, produced by the fuel pump, in a return line which opens into the fuel chamber, and which upper wall is designed with an outlet.
• the aim of the invention is to eliminate these disadvantages and to bring about a fuel system which better ensures an adequate filling of the fuel chamber at different engine loads.
• the ejector can supply a greater quantity of fuel to the fuel chamber, the greaterthe load on the engine is. This also results in a relatively small filling of the fuel chamber via the ejector during idle running when the fuel consumption is low.
• a fuel pump 3 supplies fuel to the engine 2 from a fuel tank 5 via a forward line 4.
• the fuel pump 3 is arranged in a separate fuel chamber 6 which is accommodated in the fuel tank 5 and is designed with a side wall 6' and an upper wall 6". In the fuel chamber 6, the fuel level is kept so high that the fuel pump 3 cannot suck air.
• a return line 7 for unused fuel from the engine 2 there opens on the one hand a return line 7 for unused fuel from the engine 2 and on the other hand a return line 8 which is connected to the forward line 4 and via which a part of the fuel flow from the fuel pump 3 can return to the fuel chamber 6 without passing the engine 2.
• the return line 8 there is an ejector 9 which by means of a suction line 10 can suck up fuel from the fuel tank 5 and thus forms a pump.
• the ejector 9 is driven by the return flow from the fuel pump 3 in the return line 8, the result of which is that both return fuel from the fuel pump and fresh fuel from the fuel tank are supplied to the fuel chamber 6 via the line section 11 of the return line 8, which line section is situated afterthe ejector 9.
• an outlet 12 which is made up of a relatively small opening in the upper wall 6" and via which any surplus fuel in the fuel chamber 6 can flow out into the fuel tank 5. It is desirable that, when the fuel pump is in operation, there is a fuel surplus in the fuel chamber 6 in order to ensure good pump operation, and according to the invention the fuel flows to and from the fuel chamber 6 are to be dimensioned in such a manner that a fuel surplus is obtained.
• the suction line 10 expediently opens close to the bottom of the fuel tank 5 in order to ensure good fuel supply.
• the ejector 9 can advantageously be of the type which is known through Swedish Patent Application 8703319-7, but other embodiments are also possible.
• the engine 2 is of the injection type and is provided with a number of injection nozzles 13. To regulate the fuel pressure as a function of the engine load, there is a pressure regulator 14. In the event of increasing engine load, increasing fuel pressure is required. In a fuel system in which the engine 2 has a fuel consumption of 2 l/h during idle running and 70 l/h during full-load running, it is possible according to the invention to use a fuel pump 3 which during idle running can produce a flow of 130 l/h and during full-load running a flow of 110 l/h, reduced on account of increased fuel pressure.
• the forward line 4 and the return line 8 can in this connection be dimensioned in such a manner that during idle running the fuel flow from the fuel pump is divided up so that 112 l/h are supplied to the engine while 18 l/h are supplied to the return line 8, whereas on the other hand during full-load running the fuel flow from the uel pump is divided up so that 87 l/h are supplied to the engine and 23 l/h are supplied to the return pipe 8.
• the ejector 9 will thus suck in via the suction line 10 a flow of 60 l/h during idle running and 150 l/h during full-load running.
• the fuel chamber 6 is supplied with a total flow of 188 l/h during idle running, namely 110 l/h via the return line 7 and 78 l/h via the line section 11. Since the pump capacity during idle running is 1301/h, an outflow of 58 l/h is thus obtained via the outlet 12.
• the fuel chamber 6 is supplied with a flow of 190 l/h during full-load running, namely 17 l/h via the return line 7 and 173 l/h via the line section 11. The outflow via the outlet 12 is then 80 l/h.
• the ejector 9 ensures a considerably greater fuel feed into the fuel chamber 6 from the fuel tank 5 during full-load running than during idle running. This is because during full- load running both flow and pressure in the return line 8 are greater than during idle running. Moreover, a fuel surplus in the fuel chamber 6 is ensured during full-load running, while the fuel surplus in the fuel chamber 6 can be kept at a relatively low level during idle running.
• the dimensioning of the fuel system indicated here is suitable for an engine with the selected fuel consumption, but it is of course possible, according to requirements, to dimension in another manner within the scope of the invention.

Landscapes

• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Jet Pumps And Other Pumps (AREA)
• Cooling, Air Intake And Gas Exhaust, And Fuel Tank Arrangements In Propulsion Units (AREA)
• Fuel-Injection Apparatus (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (1)

Family

ID=20379331

Family Applications (1)

Country Status (4)

Cited By (5)

Citations (5)

• 1990
  • 1990-04-27 SE SE9001541A patent/SE9001541L/ not_active Application Discontinuation
• 1991
  • 1991-04-25 EP EP19910909287 patent/EP0526574A1/en not_active Withdrawn
  • 1991-04-25 WO PCT/SE1991/000296 patent/WO1991017355A1/en not_active Application Discontinuation
  • 1991-04-25 JP JP91508556A patent/JPH05508896A/ja active Pending

Patent Citations (5)

Non-Patent Citations (2)

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