FR2722542A1 - FUEL SUPPLY SYSTEM FOR TWO-STROKE INJECTION ENGINES - Google Patents

Abstract

A fuel supply system (11) for an internal combustion engine comprising a remote fuel tank (41), first and second sump-actuated fuel pumps (13, 15) respectively comprising a fuel pumping chamber (23). ) comprising a fuel inlet (25) and a fuel outlet (27), a vapor separator (51) comprising a fuel inlet (55) communicating with the outlet (27) of the first pump (13), an outlet vapor outlet (59), a liquid fuel outlet (57), and a return fuel inlet (61), and a fuel outlet (27), and a fuel injector (71) including a nozzle (72) ) adapted to communicate with a combustion chamber, a fuel inlet (73) communicating with the fuel outlet (27) of the second pump (15), and a return outlet (77) communicating with the fuel inlet of return (61) from the vapor separator (51).

Description

i

FUEL SUPPLY SYSTEM

FOR TWO-STROKE INJECTION ENGINES

  The present invention generally relates to two-stroke internal combustion injection engines, and, in particular,

  power systems for such motors.

  Attention will be paid to the following U.S. patents 4,093,403 Schrimpf et al. 4,096,692 Nakamura et al. 4,395,995 Crain 4,562,820 Jiminez 4,732,131 Hensel 5,137, 002 Mahoney et al. The present invention provides a system for supplying

  fuel for an internal combustion engine comprising a fuel

  see distant fuel, a first fuel pump activated

  crankcase-driven including a fuel pumping chamber

  rant with a fuel inlet communicating with the fuel

  fuel supply and a fuel outlet, a vapor separator comprising a fuel inlet communicating with the outlet of the first fuel pump, a steam outlet

  fuel, a liquid fuel outlet, and a fuel inlet

  rant of return, a second fuel pump activated by car-

  ter comprising a fuel inlet communicating with the outlet of the vapor separator, and a fuel outlet, and a

  fuel injector comprising a nozzle suitable for communication

  quer with a combustion chamber, a fuel inlet communicating with the fuel outlet of the second fuel pump, and a return outlet communicating with the fuel inlet

  return fuel from the vapor separator.

  The present invention also provides a feeding system.

  fuel ration for internal combustion engine comprising

  a distant fuel tank, a first fuel pump

  rant actuated by housing comprising a membrane defining a pressure chamber adapted to be connected to a source of

  pulsating pressure and a fuel pumping chamber

  carrying a fuel inlet communicating with the fuel tank and a fuel outlet, a vapor separator comprising a fuel inlet communicating with the outlet

  from the first fuel pump, a fuel vapor outlet

  rant, a liquid fuel outlet, and a fuel inlet

  return, a second fuel pump actuated by crankcase

  taking a membrane defining a suitable pressure chamber

  ted to be connected to a pulsating pressure source and a chamber

  fuel pumping bre including fuel inlet

  communicating with the outlet of the vapor separator, and an outlet

  fuel tie, a connecting member connecting the membranes

  for a common movement, and a compressed fuel injector

  nant a nozzle adapted to communicate with a control chamber

  bustion, a fuel inlet communicating with the outlet of

  fuel from the second fuel pump, and a fuel outlet

  tower communicating with the return fuel inlet of the separa-

steam generator.

  Other features and advantages of the present invention

  tion will appear to those skilled in the art in the light of the description

  The following detailed description, claims and drawings.

  Figure 1 is a schematic view of a power system

  fuel achieving various characteristics of the pre-

invention.

  Before an embodiment of the present invention is described in detail, it is understood that the present invention is not limited in its application to the details of construction and

  parts arrangements presented in the following description or

  illustrated in the drawings. The present invention is capable of

  very embodiments and to be put into practice or achieved in various ways. In addition, it is understood that the phraseology and

  terminology is used here only for descriptive purposes

  tion and should not be considered as limiting.

  In the drawings is illustrated a supply system

  burant 11 for an internal combustion engine (not shown).

  The system 1 1 comprises first and second fuel pumps actuated by pressure from the casing 13 and 15 which can

  be of any suitable construction and which includes

  respectively membranes 17 which define cham-

  pressure bres 21 and respective fuel pumping chambers 23, and which are connected for a common movement by a suitable connection member 18. The pressure chambers 21 are connected respectively by conduits or channels 24 to a

  appropriate casing (not shown) of the associated two-stroke engine.

  Each of the fuel pumping chambers 23 includes a

  fuel inlet 25 and fuel outlet 27.

  The system 11 also includes a fuel tank 41 which can be of any suitable construction and which

  is located away from the first fuel pump 13 and which is re-

  linked to the fuel inlet 25 of the first fuel pump

  13 through a fuel line or fuel line 43.

  The system 11 also includes a vapor separator 51 which can be of any suitable construction and which includes a tank or container 53 and includes a fuel inlet 55 located near the top of the tank 53, an outlet for

  liquid fuel 57 located near the bottom of the tank 53, an outlet

  fuel vapor tie 59 located at the top of the tank 53, and a return fuel inlet 61 located midway between

  the top and bottom of the tank 53.

  The fuel inlet 55 is connected by a conduit or a connector.

  fuel line 63 at the fuel outlet 27 of the first fuel pump 13. The liquid fuel outlet 57 is connected by a fuel line or pipe 65 with the fuel inlet 25 of the second fuel pump 1 5. Leaving

  fuel vapor 59 is connected by a conduit or channel ap-

  property 67 at the air intake (not shown) of the associated engine.

  The system 11 also includes a plurality of fuel injectors 71 which can be of any construction

  appropriate and which respectively comprise a nozzle 72 adapted

  tee to distribute fuel to a combustion chamber (not re-

  shown), a fuel inlet 73 connected by a conduit or a

  fuel line 75 with fuel outlet 27 of the se-

  fuel pump line 15, and a fuel return outlet 77 connected by a fuel line or line 79 to the inlet

  return fuel 61 from the vapor separator 51.

  In use, the pulsating pressures produced in the crankcase of the associated two-stroke engine are applied to the pressure chambers 21 of the fuel pumps 13 and 15 to drive the membranes 17 back and forth in order to cause pumping of fuel by the first fuel pump 13 of the

  distant fuel tank at the fuel inlet 55 of the sepa-

  steam generator 51. Such back and forth of the membranes 17 entrainment

  also an actuation of the second pump 15 for vacuum

  rer the liquid (solid) fuel (without vapor) from the tank 53 of the vapor separator 51 and distribute said fuel to the inlets

  73 of fuel injectors 71 at a pressure

  raw about 0.7 bar (10 lbs). Fuel in excess of quantity

  required by the nozzles 72 of the fuel injectors 71 is

  led to the tank 53 of the vapor separator 51 via the pipe

  fuel return 79. Such recirculation of the fuel

  excess fuel is used to cool the fuel injectors 71.

  As a result of the above construction, the first fuel pump 13 is capable of raising the fuel from

  the remote tank 41 and to distribute said fuel to a press-

  relatively low pressure at the vapor separator 51 which serves to remove fuel from any vapor so that the fuel supplied to the fuel injectors 71 from the second fuel pump 15 is solid, i.e. without vapor. In addition, the second fuel pump 1 5 puts sufficient pressure on the fuel to such an extent that the formation of vapor from

  fuel is substantially avoided. In addition, as mentioned-

  born previously, the system 11 is designed so that the car-

  excess fuel is distributed to the fuel injectors 71, this

  which forms a fuel stream which recirculates or returns to the separa-

  steam generator 51 and which is used to cool the fuel injectors

  burant 71. Such cooling also serves to minimize the

  risk of fuel vapor reformation.

Claims (4)

  1. Fuel supply system (11) for a combustion engine   internal bustion comprising a remote fuel tank (41),   a first fuel pump (13) actuated by a crankcase   taking a fuel pumping chamber (23) having a fuel inlet (25) communicating with said fuel tank (41) and a fuel outlet (27), a fuel separator   steam (51) comprising a fuel inlet (55) communicating   as for said outlet (27) of said first fuel pump   rant (13), a fuel vapor outlet (59), a liquid fuel outlet (57), and a return fuel inlet (61),   a second fuel pump (1 5) actuated by a sump   nant a fuel inlet (25) communicating with said outlet (57) of said vapor separator (51), and a fuel outlet (27), and a fuel injector (71) comprising a nozzle (72) adapted to communicate with a combustion chamber, a fuel inlet (73) communicating with said fuel outlet (27) of said second fuel pump (1 5), and a fuel outlet   return (77) communicating with said return fuel inlet   tower (61) of said vapor separator (51).   2. The fuel supply system according to claim 1, wherein said first and second fuel pumps (13,   ) respectively comprise membranes (17) which are re-   linked by a connecting member (18) for a common movement.   The fuel supply system according to claim 1, and further comprising a plurality of fuel injectors (71).   4. Fuel system for combustion engine   internal tion comprising a remote fuel tank (41),   a first fuel pump (1 3) actuated by a crankcase   taking a membrane (17) defining a pressure chamber (21) adapted to be connected to a pulsating pressure source and a fuel pumping chamber (23) having a fuel inlet (25) communicating with said fuel tank (41 ) and a fuel outlet (27), a vapor separator (51)   comprising a fuel inlet (55) communicating with ladi-   the outlet (27) of said first fuel pump (13), a fuel vapor outlet (59), a liquid fuel outlet (57), and a return fuel inlet (61), a second fuel pump (15) actuated by housing comprising a membrane   (17) defining a pressure chamber (21) adapted to be re-   linked to a pulsating pressure source and a pumping chamber   fuel tank (23) comprising a fuel inlet (25) communicating with said outlet (57) of said vapor separator (51), and a fuel outlet (27), a connection member (18) connecting said membranes (17 ) for a common movement, and a fuel injector (71) comprising a nozzle (72) adapted to   communicate with a combustion chamber, a fuel inlet   burant (73) communicating with said fuel outlet (27) of said second fuel pump (1 5), and a return outlet (77) communicating with said return fuel inlet (61) said vapor separator (51).