Fuel injection nozzle for internal combustion engines

• US 4,982,708 A
• Filed: 02/12/1990
• Issued: 01/08/1991
• Est. Priority Date: 06/22/1989
• Status: Expired due to Fees

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Stutzenberger, Heinz
• Primary Examiner(s): Argenbright, Tony M.
• Application Number:
  US07/478,319
• Time in Patent Office: 330 Days
• Field of Search: 123/297, 123/298, 123/169 V, 313/120, 239/533.3-533.12, 239/453, 239/456
• US Class Current: 123/297
• CPC Class Codes: F02B 1/04 with fuel-air mixture admission into cylinder
• CPC Class Codes: F02B 2075/125 Direct injection in the combustion chamber for spark ignition engines, i.e. not in pre-combustion chamber
• CPC Class Codes: F02M 57/06 the devices being sparking plugs
• CPC Class Codes: F02M 61/08 the valves opening in direction of fuel flow F02M61/047 takes precedence
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

A fuel injection nozzle that produces a non-symmetrical conical stream in an eccentrically and obliquely installed fuel injection nozzle for a engine. The fuel injection nozzle body is formed with a conical end in which the center axis of the conical wall face forming the valve seat on the nozzle body is disposed at an angle (a) to the axis of the valve needle, and that a sealing face on the closing head of the valve needle that cooperates with the valve seat on the nozzle body is spherically curved.

Claims

1. A fuel injection nozzle for internal combustion engines, having a valve needle, a nozzle body (38) having an injection end, said nozzle body is provided with a central bore that receives and guides said valve needle, said central bore merges on a nozzle body face end toward the injection end with a wall face (50) that expands conically outward to form a valve seat (76), said valve needle including a closing head which closes against said wall face end, said closing head is pressed against the valve seat by a closing spring counter to a flow direction of an injection fuel delivered through said central bore, said conical wall face (50) forming the valve seat (76) is disposed on the nozzle body (38) on a center axis which is at an angle (a) to the longitudinal axis (72) of the valve needle (42) and said closing head (44) of the valve needle (42) includes a spherically curved sealing face (74) that cooperates with the valve seat (76) on the nozzle body (38) to form an emerging conical fuel injection stream (80).

2. An injection nozzle as defined by claim 1, in which at least one pair of electrodes (64, 66) is provided on the injection end of the fuel injection nozzle in a vicinity of the conical stream (80) of the emerging injection fuel which forms a spark gap of an ignition device for an internal combustion engine with externally supplied ignition.

3. An injection nozzle as defined by claim 2, in which said fuel injection nozzle includes a retaining body, by way of which said nozzle body is secured on said retaining body which can be connected to the cylinder head of the engine, and one electrode (66) of the spark gap is secured to the retaining body (26) and another electrode (64) is secured to the nozzle body (38), which is connected to the retaining body (26) via an insulating body (30).

4. An injection nozzle as defined by claim 2, in which at least one pair of electrodes (64, 66) is disposed in a circumferential region of the conical stream (80) in which, with externally supplied ignition, a most favorable fuel-to-air ratio prevails over a wide operating range.

5. An injection nozzle as defined by claim 3, in which at least one pair of electrodes (64, 66) is disposed in a circumferential region of the conical stream (80) in which, with externally supplied ignition, a most favorable fuel-to-air ratio prevails over a wide operating range.

6. A fuel injection nozzle as set forth in claim 1 in which said longitudinal axis of said valve nozzle is coaxial with said central bore.