Claims
- 1. An injector for a fuel injection system for internal combustion engines, comprising a pressure booster (19) having a first piston (9) guided in a first guide bore (5) and a second piston (11) guided in a second guide bore (7), wherein the first piston (9) and the second piston (11) define a pressure chamber (17) that is under at least a supply pressure, and having a leaking oil return line (25), wherein the first piston (9) is actuated by an actuator (21) and the second piston (11) at least indirectly actuates the final control element (15) of a control valve, said second guide bore (7) communicates hydraulically with said leaking oil return (25), the pressure p1 in the leaking oil return (25) being lower than the supply pressure.
- 2. The injector of claim 1, wherein the first guide bore (5), the first piston (9) and the housing (1, 3) are sealed off from their surroundings.
- 3. The injector of claim 2, further comprising a bellows (33) sealing off said first guide bore (5), said first piston (9) and said housing (1, 3) from their surroundings.
- 4. The injector of claim 2, wherein the supply pressure in the pressure chamber (17) is furnished by a supply line (31) discharging into the chamber (34) formed by the housing (1, 3), bellows (33) and first piston.
- 5. The injector of claim 1, further comprising a pressure holding valve (37) disposed in the supply line (31).
- 6. The injector of claim 5, wherein said pressure holding valve (37) limits the pressure p2 in the supply line (31) to about 50 bar.
- 7. The injector of claim 1, further comprising a recess (29) which is in communication with the leaking oil return (25) is present at the second guide bore (7).
- 8. The injector of claim 1, wherein said second piston (11) actuates the final control element (15) of the control valve via a tappet (13).
- 9. The injector of claim 1, wherein the control valve discharges into the leaking oil return (25).
- 10. The injector of claim 1, wherein the actuator is a piezoelectric actuator (21).
- 11. The injector of claim 1, wherein the housing (1, 3), the control valve, and the actuator (21) are mounted in a retaining body (35).
- 12. A fuel injection system for internal combustion engines, including a high-pressure fuel pump, a high pressure fuel reservoir, and at least one injector said injector comprising a pressure booster (19) having a first piston (9) guided in a first guide bore (5) and a second piston (11) guided in a second guide bore (7), wherein the first piston (9) and the second piston (11) define a pressure chamber (17) that is under at least a supply pressure, and having a leaking oil return line (25), wherein the first piston (9) is actuated by an actuator (21) and the second piston (11) at least indirectly actuates the final control element (15) of a control valve, said second guide bore (7) communicates hydraulically with said leaking oil return (25), the pressure p1 in the leaking oil return (25) being lower than the supply pressure.
- 13. The injector of claim 3, wherein the supply pressure in the pressure chamber (17) is furnished by a supply line (31) discharging into the chamber (34) formed by the housing (1, 3), bellows (33) and first piston.
- 14. The injector of claim 4, further comprising a pressure holding valve (37) disposed in the supply line (31).
- 15. The injector of claim 13, further comprising a pressure holding valve (37) disposed in the supply line (31).
- 16. The injector of claim 13, wherein said pressure holding valve (37) limits the pressure p2 in the supply line (31) to about 50 bar.
- 17. The injector of claim 2, further comprising a recess (29) which is in communication with the leaking oil return (25) is present at the second guide bore (7).
- 18. The injector of claim 2, wherein said second piston (11) actuates the final control element (15) of the control valve via a tappet (13).
- 19. The injector of claim 2, wherein the control valve discharges into the leaking oil return (25).
- 20. The injector of claim 4, wherein the actuator is a piezoelectric actuator (21).
- 21. The injector of claim 4, wherein the housing (1, 3), the control valve, and the actuator (21) are mounted in a retaining body (35).
Priority Claims (1)
Number |
Date |
Country |
Kind |
199 51 144 |
Oct 1999 |
DE |
|
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a 35 USC 371 application of PCT/DE 00/03582 filed on Oct. 12, 2000.
PCT Information
Filing Document |
Filing Date |
Country |
Kind |
PCT/DE00/03582 |
|
WO |
00 |
Publishing Document |
Publishing Date |
Country |
Kind |
WO01/31192 |
5/3/2001 |
WO |
A |
US Referenced Citations (6)
Foreign Referenced Citations (3)
Number |
Date |
Country |
198 07 903 |
Sep 1999 |
DE |
0 826 876 |
Mar 1998 |
EP |
0 890 730 |
Jan 1999 |
EP |