Fuel injection rate control system for an internal combustion engine

• US 4,542,725 A
• Filed: 07/31/1984
• Issued: 09/24/1985
• Est. Priority Date: 08/17/1983
• Status: Expired due to Term

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Yasuhara, Seishi
• Primary Examiner(s): Lazarus, Ira S.
• Assistant Examiner(s): Okonsky, David A.
• Application Number:
  US06/636,413
• Time in Patent Office: 420 Days
• Field of Search: 123/299, 123/300, 123/449, 123/458, 123/179 L
• US Class Current: 123/299
• CPC Class Codes: F02B 3/06 with compression ignition compression ignition engines using air or gas for blowing fuel into compressed air in cylinder F02B13/02
• CPC Class Codes: F02D 2200/0602 Fuel pressure
• CPC Class Codes: F02D 41/402 Multiple injections
• CPC Class Codes: F02D 41/403 with pilot injections
• CPC Class Codes: F02D 41/408 of the distributing type
• CPC Class Codes: F02M 41/12 the pistons rotating to act as the distributor
• CPC Class Codes: F02M 41/123 characterised by means for varying fuel delivery or injection timing
• CPC Class Codes: F02M 45/06 Pumps peculiar thereto
• CPC Class Codes: F02M 63/02 Fuel-injection apparatus having several injectors fed by a common pumping element, or having several pumping elements feeding a common injector; Fuel-injection apparatus having provisions for cutting-out pumps, pumping elements, or injectors; Fuel-injection apparatus having provisions for variably interconnecting pumping elements and injectors alternatively
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A first pump serves to periodically inject fuel into a combustion chamber of an internal combustion engine at a first timing in terms of crankshaft rotation, i.e., crank angle. A second pump serves to periodically inject fuel into the combustion engine at the first timing and also at a second timing in terms of crank angle. The second timing precedes the first timing. The rate of fuel injection by the second pump at the first timing is inversely related to the rate of fuel injection by the second pump at the second timing.

Claims

1. A fuel injection control system for an internal combustion engine having a crankshaft and a combustion chamber, comprising:

(a) first means for periodically injecting fuel into the combustion chamber at a first timing within an engine cycle with respect to rotation of the crankshaft; and

(b) second means for periodically injecting fuel into the combustion chamber at the first timing and also at a second timing within said engine cycle with respect to rotation of the crankshaft, the second timing preceding the first timing, the rate and quantity of fuel injection by the second means at the first timing being dependently and inversely related to the rate and quantity of fuel injection by the second means at the second timing.

2. The system of claim 1, including dependently operated valve means for controlling the rate of fuel injection by the second means at the first timing to increase from zero to its maximum and to decrease from its maximum to zero as the rate and quantity of fuel injection by the second means at the second timing decreases from its maximum to zero and increases from zero to its maximum, respectively.

3. The system of claim 1, further comprising:

(a) means for sensing the load on the engine; and

(b) means for increasing the rate and quantity of fuel injection by the second means at the first timing and thus decreasing the rate of fuel injection by the second means at the second timing as the sensed engine load increases.

4. The system of claim 1, further comprising:

(a) means for sensing the speed of rotation of the crankshaft; and

(b) means for increasing the rate and quantity of fuel injection by the second means at the first timing and thus decreasing the rate and quantity of fuel injection by the second means at the second timing as the sensed crankshaft speed increases.

5. A fuel injection control system for an internal combustion engine having a rotatable crankshaft and at least two combustion chambers operating at the same frequency and at different phases with respect to each other, the system comprising:

(a) a plunger free to reciprocate;

(b) means for reciprocating the plunger as the crankshaft rotates;

(c) a member defining a first pressure chamber in conjunction with the plunger, the first pressure chamber contracting and expanding as the plunger reciprocates;

(d) means for conducting fuel to the first pressure chamber as the first pressure chamber expands;

(e) means for conducting fuel from the first pressure chamber to each of the combustion chambers in turn to effect first fuel injection thereinto each time the first pressure chamber contracts;

(f) a member defining a second pressure chamber in conjunction with the plunger, the second pressure chamber contracting and expanding as the plunger reciprocates;

(g) means for conducting fuel to the second pressure chamber as the second pressure chamber expands;

(h) means for conducting fuel out of the second pressure chamber as the second pressure chamber contracts;

(i) means for dividing fuel from the second pressure chamber into first and second portions;

(j) means for conducting the first portion of fuel to the first pressure chamber; and

(k) means for conducting the second portion of fuel to each of the combustion chambers in turn to effect second fuel injection thereinto, the combustion chamber which is receiving the second fuel injection operating prior to the combustion chamber which is receiving the first fuel injection.

6. The system of claim 5, further comprising:

(a) means for sensing the load on the engine; and

(b) means for increasing the first portion of fuel and thus decreasing the second portion of fuel as the sensed engine load increases.

7. The system of claim 5, further comprising:

(a) means for sensing the speed of rotation of the crankshaft; and

(b) means for increasing the first portion of fuel and thus decreasing the second portion of fuel as the sensed crankshaft speed increases.

8. The system of claim 5, further comprising means for disabling delivery of part of the second portion of fuel to the combustion chamber.

9. The system of claim 8, further comprising:

(a) means for sensing the load on the engine; and

(b) means for increasing the disabled part of the second portion of fuel as the sensed engine load increases.

10. The system of claim 5, further comprising means for adjusting the rate and quantity of fuel delivery to the second pressure chamber.

11. The system of claim 10, further comprising:

(a) means for sensing the load on the engine; and

(b) means for increasing the rate and quantity of fuel delivery to the second pressure chamber as the sensed engine load decreases.

12. The system of claim 10, further comprising:

(a) means for sensing the speed of rotation of the crankshaft; and

(b) means for increasing the rate and quantity of fuel delivery to the second pressure chamber as the sensed crankshaft speed decreases.