BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic plan view of an eight cylinder, V-type internal combustion engine having a sequential firing order of 1-2-7-8-4-5-6-3 and illustrating an intake manifold assembly consistent with the present invention;
FIG. 2 is a schematic plan view of an eight cylinder, V-type internal combustion engine have a sequential firing order of 1-5-6-3-4-2-7-8 and illustrating an alternate embodiment of the intake manifold assembly of the present invention;
FIG. 3 is a schematic plan view of an eight cylinder, V-type internal combustion engine have a sequential firing order of 1-2-7-3-4-5-6-8 and illustrating an alternate embodiment of the intake manifold assembly of the present invention;
FIG. 4 is a schematic plan view of an eight cylinder, V-type internal combustion engine have a sequential firing order of 1-2-6-3-4-5-7-8 and illustrating an alternate embodiment of the intake manifold assembly of the present invention;
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the drawings wherein like reference numbers correspond to like or similar components throughout the several figures, there is shown in FIG. 1 an internal combustion engine 10. The internal combustion engine 10 may be either a spark-ignited type or a compression-ignited type. For discussion hereinbelow, it will be assumed that the internal combustion engine 10 is a compression-ignited internal combustion engine. The internal combustion engine 10 includes a cylinder case or block 12 having a first bank of cylinders 14 and a second bank of cylinders 16. The first and second bank of cylinders 14 and 16 are arranged in a generally V-shaped configuration such that the internal combustion engine 10 may be characterized as a V-type internal combustion engine. The space at least partially defined by the included angle of the first and second bank of cylinders 14 and 16 is generally referred to as a valley 18.
Each of the first and second bank of cylinders 14 and 16 define a plurality of cylinders 20. Each of the cylinders 20 defined by the first bank of cylinders 14 are arranged from a first end of the internal combustion engine 10 to a second end of the internal combustion engine 10 as first cylinder 1, third cylinder 3, fifth cylinder 5, and seventh cylinder 7. Similarly, each of the cylinders 20 defined by the second bank of cylinders 16 are arranged from the first end of the internal combustion engine 10 to the second end of the internal combustion engine 10 as second cylinder 2, fourth cylinder 4, sixth cylinder 6, and eighth cylinder 8. As such, the internal combustion engine 10 may be further characterized by having eight cylinders 20.
The internal combustion engine may further include an intake manifold assembly 22. The intake manifold assembly is operable to provide intake air 24 to the cylinders 20 of the internal combustion engine 10 to enable combustion of fuel, not shown, within the cylinders 20. The intake manifold assembly 22 includes an intake air duct 26 in fluid communication with a first flow passage and a second flow passage 28 and 30, respectively. The first flow passage 28 is in fluid communication with a first plenum runner 32 and a second plenum runner 34. The first plenum runner 32 is operable to communicate intake air 24 to a first plenum 36 for subsequent introduction to at least one of the first cylinder 1, third cylinder 3, fifth cylinder 5, and seventh cylinder 7. The second plenum runner 34 is operable to communicate intake air 24 to a second plenum 38 for subsequent introduction to the at least one of the first cylinder 1, third cylinder 3, fifth cylinder 5, and seventh cylinder 7 that is not in fluid communication with the first intake plenum 36.
The second flow passage 30 is in fluid communication with a third plenum runner 40 and a fourth plenum runner 42. The third plenum runner 40 is operable to communicate intake air 24 to a third plenum 44 for subsequent introduction to at least one of the second cylinder 2, fourth cylinder 4, sixth cylinder 6, and eighth cylinder 8. The fourth plenum runner 42 is operable to communicate intake air 24 to a fourth plenum 46 for subsequent introduction to the at least one of the second cylinder 2, fourth cylinder 4, sixth cylinder 6, and eighth cylinder 8 that is not in fluid communication with the third intake plenum 44.
As illustrated in FIG. 1, the first and second intake plenum 36, and 38 are mounted in an outboard position with respect to the internal combustion engine 10. That is, the first and second intake plenum 36 and 38 are disposed substantially adjacent to the first bank of cylinders 14 opposite the valley 18. Similarly, the third and fourth intake plenum 44 and 46 are mounted in an outboard position with respect to the internal combustion engine 10. That is, the third and fourth intake plenum 44 and 46 are disposed substantially adjacent to the second bank of cylinders 16 opposite the valley 18. A compressor 48, such as a turbocharger or a supercharger, may be provided in fluid communication with the intake manifold assembly 22, and operate to selectively pressurize the intake air 24 within the intake manifold assembly 22.
The intake manifold assembly 22 as shown in FIG. 1 is configured for a sequential cylinder firing sequence of the first cylinder 1, second cylinder 2, seventh cylinder 7, eighth cylinder 8, fourth cylinder 4, fifth cylinder 5, sixth cylinder 6, and third cylinder 3, or what is commonly referred to as a 1-2-7-8-4-5-6-3 firing order. With this configuration, the close firing pair of cylinders 20 on the first bank of cylinders 14 are the third cylinder 3 and the first cylinder 1. The first intake plenum 36 is configured to communicate intake air 24 to the first cylinder 1, and the second intake plenum 38 is configured to communicate intake air to the third cylinder 3, fifth cylinder 5, and seventh cylinder 7. The close firing pair of cylinders 20 on the second bank of cylinders 16 are the eighth cylinder 8 and the fourth cylinder 4. The third intake plenum 44 is configured to communicate intake air 24 to the second cylinder 2 and fourth cylinder 4, and the fourth intake plenum 46 is configured to communicate intake air to the sixth cylinder 6 and eighth cylinder 8. By configuring the intake manifold assembly 22 in this way, the tuning effects of the close firing pair of cylinders 20 on each of the first and second bank of cylinders 14 and 16 may be substantially attenuated.
Referring now to FIG. 2 there is shown the internal combustion engine 10 having an alternate embodiment of the intake manifold assembly 22, shown in FIG. 1, and generally indicated as 22A. The intake manifold assembly 22A is configured for a sequential cylinder firing sequence of the first cylinder 1, fifth cylinder 5, sixth cylinder 6, third cylinder 3, fourth cylinder 4, second cylinder 2, seventh cylinder 7, eighth cylinder 8, or what is commonly referred to as a 1-5-6-3-4-2-7-8 firing order. With this configuration, the close firing pair of cylinders 20 on the first bank of cylinders 14 are the first cylinder 1 and the fifth cylinder 5. The first intake plenum 36 is configured to communicate intake air 24 to the first cylinder 1, and the third cylinder 3, and the second intake plenum 38 is configured to communicate intake air 24 to the fifth cylinder 5 and seventh cylinder 7. The close firing pair of cylinders 20 on the second bank of cylinders 16 are the fourth cylinder 4 and the second cylinder 2. The third intake plenum 44 is configured to communicate intake air 24 to the second cylinder 2, and the fourth intake plenum 46 is configured to communicate intake air 24 to the fourth cylinder 4, sixth cylinder 6, and eighth cylinder 8. By configuring the intake manifold assembly 22A in this way, the tuning effects of the close firing pair of cylinders 20 on each of the first and second bank of cylinders 14 and 16 may be substantially attenuated.
Referring now to FIG. 3 there is shown the internal combustion engine 10 having an alternate embodiment of the intake manifold assembly 22, shown in FIG. 1, and generally indicated as 22B. The intake manifold assembly 22B is configured for a sequential cylinder firing sequence of the first cylinder 1, second cylinder 2, seventh cylinder 7, third cylinder 3, fourth cylinder 4, fifth cylinder 5, sixth cylinder 6, and eighth cylinder 8, or what is commonly referred to as a 1-2-7-3-4-5-6-8 firing order. With this configuration, the close firing pair of cylinders 20 on the first bank of cylinders 14 are the seventh cylinder 7 and the third cylinder 3. The first intake plenum 36 is configured to communicate intake air 24 to the first cylinder 1, and the third cylinder 3, and the second intake plenum 38 is configured to communicate intake air 24 to the fifth cylinder 5 and seventh cylinder 7. The close firing pair of cylinders 20 on the second bank of cylinders 16 are the sixth cylinder 6 and the eight cylinder 8. The third intake plenum 44 is configured to communicate intake air 24 to the fourth cylinder 4, sixth cylinder 6, and eighth cylinder 8, and the fourth intake plenum 46 is configured to communicate intake air 24 to the second cylinder 2. By configuring the intake manifold assembly 22B in this way, the tuning effects of the close firing pair of cylinders 20 on each of the first and second bank of cylinders 14 and 16 may be substantially attenuated.
Referring now to FIG. 4 there is shown the internal combustion engine 10 having an alternate embodiment of the intake manifold assembly 22, shown in FIG. 1, and generally indicated as 22C. The intake manifold assembly 22C is configured for a sequential cylinder firing sequence of the first cylinder 1, second cylinder 2, sixth cylinder 6, third cylinder 3, fourth cylinder 4, fifth cylinder 5, seventh cylinder 7, and eight cylinder 8, or what is commonly referred to as a 1-2-3-4-5-7-8 firing order. With this configuration, the close firing pair of cylinders 20 on the first bank of cylinders 14 are the fifth cylinder 5 and the seventh cylinder 7. The first intake plenum 36 is configured to communicate intake air 24 to the first cylinder 1, third cylinder 3, and fifth cylinder 5, and the second intake plenum 38 is configured to communicate intake air 24 to the seventh cylinder 7. The close firing pair of cylinders 20 on the second bank of cylinders 16 are the second cylinder 2 and the sixth cylinder 6. The third intake plenum 44 if configured to communicate intake air 24 to the second cylinder 2 and fourth cylinder 4, and the fourth intake plenum 46 is configured to communicate intake air 24 to the sixth cylinder 6 and eighth cylinder 8. By configuring the intake manifold assembly 22C in this way, the tuning effects of the close firing pair of cylinders 20 on each of the first and second bank of cylinder 14 and 16 may be substantially attenuated.
By effectively separating the flow path of intake air 24 to the close firing pair of cylinders 20 on each of the first and second banks of cylinders 14 and 16, the cylinder-to-cylinder combustion variation of the internal combustion engine 10 may be substantially reduced. This reduction in variation may improve power density and exhaust emissions of the internal combustion engine 10.
While the best modes for carrying out the invention have been described in detail, those familiar with the art to which this invention relates will recognize various alternative designs and embodiments for practicing the invention within the scope of the appended claims.
Patent Application
20080034852
