Outboard motor powerhead section and fuel delivery system having low-profile fuel rail
10161368 ยท 2018-12-25
Assignee
Inventors
Cpc classification
F02M35/104
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02M55/025
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
B63H20/001
PERFORMING OPERATIONS; TRANSPORTING
F02B61/045
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02M61/18
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02M57/04
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02F1/4235
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02M63/0275
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
B63H20/00
PERFORMING OPERATIONS; TRANSPORTING
F02M69/465
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02M35/10216
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02M61/145
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
International classification
F02M61/00
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02M61/18
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02M37/00
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02F1/42
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
B63H20/00
PERFORMING OPERATIONS; TRANSPORTING
F02M57/04
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02M55/02
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02B61/04
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02M35/10
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
Abstract
An outboard motor powerhead section includes an engine having vertically stacked cylinders. The engine includes intake passages extending through the cylinder head to the cylinders. A fuel rail extends along a vertical center axis alongside the cylinder head. Receiver cups are coupled to the fuel rail and vertically spaced from one another such that each receiver cup is associated with a respective cylinder. Each receiver cup has a respective connector passage providing fluid communication between the fuel rail and receiver cup. Fuel injectors are respectively coupled to the receiver cups. Each fuel injector has an inlet end located in a respective receiver cup and extends along a center axis toward a nozzle end that extends into a respective intake passage. A cowl covers the engine. The vertical center axis of the fuel rail is located relatively more inboard with respect to the engine than is at least one connector passage.
Claims
1. An outboard motor powerhead section comprising: an internal combustion engine having a cylinder head coupled to a first end of a cylinder block, the cylinder block and the cylinder head together defining vertically stacked cylinders, and having intake passages, each intake passage extending through the cylinder head to a respective cylinder; a crankcase cover coupled to a second, opposite end of the cylinder block; intake runners that extend along a side of the cylinder block from the crankcase cover to the cylinder head, each intake runner providing intake air to a respective intake passage; a fuel rail extending along a vertical center axis alongside the cylinder head; receiver cups coupled to the fuel rail and vertically spaced from one another such that each receiver cup is associated with a respective cylinder, each receiver cup having a respective connector passage providing fluid communication between the fuel rail and the receiver cup; fuel injectors respectively coupled to the receiver cups, each fuel injector having an inlet end located in a respective receiver cup and extending along a center axis toward a nozzle end that extends into a respective intake passage; and a cowl covering the engine; wherein the vertical center axis of the fuel rail is located relatively more inboard with respect to the engine than is at least one connector passage; and wherein the fuel rail is located between the intake runners and a nearest inner surface of the cowl.
2. The powerhead section of claim 1, wherein an outboard-most outer surface of the fuel rail is further from the nearest inner surface of the cowl than are outboard-most outer ends of the receiver cups.
3. The powerhead section of claim 2, further comprising a cylinder head cover coupled to the cylinder head, wherein the fuel rail, the receiver cups, and the fuel injectors are located inboard of a filleted curve connecting an outer extent of the intake runners with an outer extent of the cylinder head cover.
4. The powerhead section of claim 2, wherein each receiver cup comprises a tubular body portion having an open end for receiving the respective fuel injector and an opposite, closed end including a port communicating with the respective connector passage.
5. The powerhead section of claim 4, wherein the center axis of each fuel injector is oriented at an angle of less than 180 degrees with respect to a respective center axis of the port in the body portion of each receiver cup.
6. The powerhead section of claim 5, wherein the center axis of each fuel injector is horizontal and is perpendicular to the respective center axis of the port in the body portion of each receiver cup.
7. The powerhead section of claim 6, wherein the outboard-most outer end of each receiver cup is further outboard than the center axis of the port in the body portion of each receiver cup.
8. The powerhead section of claim 7, wherein a horizontal distance between the vertical center axis of the fuel rail and the outboard-most outer end of each receiver cup is between about 13 millimeters and about 16 millimeters.
9. The powerhead section of claim 1, wherein each connector passage is integral with each respective receiver cup.
10. A fuel delivery system for an outboard motor internal combustion engine having a cylinder head coupled to a first end of a cylinder block, the cylinder block and the cylinder head together defining stacked cylinders, and having intake passages, each intake passage extending through the cylinder head to a respective cylinder, and having a crankcase cover coupled to a second, opposite end of the cylinder block, and having intake runners that extend along a side of the cylinder block from the crankcase cover to the cylinder head, each intake runner providing intake air to a respective intake passage, the fuel delivery system comprising: a fuel rail extending along a rail center axis alongside the cylinder head; receiver cups coupled to the fuel rail and spaced from one another with respect to the rail center axis such that each receiver cup is associated with a respective cylinder, each receiver cup having a respective connector passage that extends into the fuel rail; and fuel injectors respectively coupled to the receiver cups, each fuel injector having an inlet end located in a respective receiver cup and extending along an injector center axis toward a nozzle end communicating with a respective intake passage; wherein each receiver cup includes a tubular body portion having an open end for receiving the respective fuel injector and an opposite, closed end including a port communicating with the respective connector passage; wherein the rail center axis does not intersect with the injector center axes and does not intersect with respective port center axes of the ports in the body portions of the receiver cups; wherein the rail center axis of the fuel rail is located relatively more laterally inboard with respect to the engine than is a center axis of at least one connector passage; and wherein the fuel rail is located between the intake runners and a nearest inner surface of a cowl covering the engine.
11. The fuel delivery system of claim 10, wherein outer surfaces of the closed ends of the body portions are relatively further laterally outboard with respect to the engine than are the port center axes of the ports in the body portions of the receiver cups.
12. The fuel delivery system of claim 10, wherein the injector center axis of each fuel injector is perpendicular to the respective port center axis of the port in the body portion of each receiver cup.
13. The fuel delivery system of claim 10, wherein each connector passage is integral with each respective receiver cup.
14. An outboard motor powerhead section comprising: an internal combustion engine having a cylinder head coupled to a first end of a cylinder block, the cylinder block and the cylinder head together defining vertically stacked cylinders, and having intake passages, each intake passage extending through the cylinder head to a respective cylinder; a crankcase cover coupled to a second, opposite end of the cylinder block; intake runners that extend along a side of the cylinder block from the crankcase cover to the cylinder head, each intake runner providing intake air to a respective intake passage; a fuel rail extending along a vertical center axis alongside the cylinder head; receiver cups coupled to the fuel rail and vertically spaced from one another such that each receiver cup is associated with a respective cylinder, each receiver cup having a respective connector passage providing fluid communication between the fuel rail and the receiver cup; fuel injectors respectively coupled to the receiver cups, each fuel injector having an inlet end located in a respective receiver cup and extending along a center axis toward a nozzle end that extends into a respective intake passage; and a cowl covering the engine; wherein the vertical center axis of the fuel rail is located relatively more inboard with respect to the engine than is at least one connector passage; wherein the fuel rail is located between the intake runners and an inner surface of the cowl; wherein an outboard-most outer surface of the fuel rail is further from the inner surface of the cowl than are outboard-most outer ends of the receiver cups; wherein each receiver cup comprises a tubular body portion having an open end for receiving the respective fuel injector and an opposite, closed end including a port communicating with the respective connector passage; wherein the center axis of each fuel injector is oriented at an angle of less than 180 degrees with respect to a respective center axis of the port in the body portion of each receiver cup; and wherein the center axis of each fuel injector is horizontal and is perpendicular to the respective center axis of the port in the body portion of each receiver cup.
15. The powerhead section of claim 14, wherein the outboard-most outer end of each receiver cup is further outboard than the center axis of the port in the body portion of each receiver cup.
16. The powerhead section of claim 15, wherein a horizontal distance between the vertical center axis of the fuel rail and the outboard-most outer end of each receiver cup is between about 13 millimeters and about 16 millimeters.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) The present disclosure is described with reference to the following Figures. The same numbers are used throughout the Figures to reference like features and like components.
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DETAILED DESCRIPTION
(9) In the present description, certain terms have been used for brevity, clarity and understanding. No unnecessary limitations are to be inferred therefrom beyond the requirement of the prior art because such terms are used for descriptive purposes only and are intended to be broadly construed.
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(11) A crankcase cover 22 is coupled to a second, opposite end of the cylinder block 18 and encloses a vertically oriented crankshaft 53. Two pairs of intake runners 24 extend along either side of the cylinder block 18 from the crankcase cover 22 to a respective cylinder head 16. The intake runners 24 extend from a surge take or silencer 26 located fore of the crankcase cover 22 and around the outside of the cylinder banks 19a, 19b. One intake runner 24 is provided for each of the four cylinders 20. Thus, each intake runner 24 provides intake air to a respective intake passage 38, which intake passage 38 extends through the cylinder head 16 to a respective cylinder 20, as will be described further herein below. Two fuel rails 28 are provided to carry fuel to the intake passages 38 in the cylinder heads 16. Each fuel rail 28 extends along a respective vertical center axis 30 alongside each respective cylinder head 16. Each fuel rail 28 is located between a respective pair of intake runners 24 and an inner surface 32 of the cowl 14.
(12) The fuel delivery system 33 for the engine 12 also includes a fuel source 34 that is in fluid communication with the fuel rails 28 by way of a fuel filter 35 and a fuel pump 36. This may be through a variety of different hoses, tubes, and the like. Additionally, a fuel reservoir, a high pressure pump, a low pressure pump, vapor separator, fuel supply module, and/or pressure sensors may be provided as part of the fuel delivery system 33 as known to those having ordinary skill in the art. Fuel return lines may also be provided to return fuel to the fuel source 34. The exact components and layout provided for the fuel source, reservoir, pump(s), etc. are ancillary to the details of the fuel delivery system 33 of the present disclosure, and are not limiting on the scope of the present claims. Briefly, in the example shown, the fuel pump 36 provides fuel at high pressure to each of the fuel rails 28, after which the flow of fuel is guided through receiver cups and fuel injectors of the fuel delivery system 33, as will be described below.
(13) As mentioned above, the engine 12 includes a plurality of intake passages 38, each intake passage 38 extending through a respective cylinder head 16 to a respective cylinder 20. One of the intake passages 38 is shown in more detail in
(14) Intake air travels through the intake runner 24 as shown by the direction of the arrows therein, enters the intake passage 38, and thereafter enters the cylinder 20 upon retraction of the intake valve face 47 from the opening that leads into the cylinder 20. Fuel is injected into the stream of air prior to its entry into cylinder 20 by a fuel injector 48, the coupling of which to fuel rail 28 will be described further herein below. Although only one intake passage 38 and fuel injector 48 are shown herein, it should be understood that the same assembly is provided at the cylinder above or below the one shown in
(15) Referring to
(16) As mentioned, the fuel delivery system 33 includes the plurality of receiver cups, one of which is shown at 50, coupled to the fuel rail 28 and vertically spaced from one another (see
(17) The center axes 58 of each of the fuel injectors 48 are oriented at an angle of less than 180 with respect to the horizontal center axes 54 of the connector passages 52. In one example, the center axes 58 of the fuel injectors 48 are oriented at an angle of less than or approximately equal to 90 with respect to the horizontal center axes 54 of the connector passages 52. More specifically, in the example shown herein, the center axes 58 of the fuel injectors 48 are horizontal, and are perpendicular to the horizontal center axes 54 of the connector passages 52. Thus, the center axis 58 of each fuel injector 48 is also perpendicular to the respective center axis 54 of the port 65 in the body portion 60 of the receiver cup 50. Each receiver cup 50 includes the tubular body portion 60, which has an open end 62 for receiving the fuel injector 48 and an opposite, closed end 64 for receiving fuel from the connector passage 52. The closed end 64 also includes the port 65 communicating with the connector passage 52. Thus, for each receiver cup 50, the tubular adapter portion 66 is oriented at the angle of less than 180 (and in one example, is perpendicular) with respect to the body portion 60. The center axis 58 of each fuel injector 48 is thus also oriented at the angle of less than 180 degrees (and in one example, is perpendicular) with respect to the center axis 54 of the port 65 in the body portion 60 of the receiver cup 50. In the example shown, the tubular body portion 60 and the tubular adapter portion 66 are formed integrally with one another such that the connector passage 52 is integral with the receiver cup 50; however, the tubular body portion 60 and the tubular adapter portion 66 could instead be separate parts.
(18) The fuel rail 28 includes a plurality of sockets 68 extending therefrom. Each socket 68 receives a respective adapter portion 66 of a respective receiver cup 50 therein. Thus, there is the same number of sockets 68 provided as there are cylinders 20 and fuel injectors 48. Each socket 68 in the plurality of sockets is integral with the fuel rail 28. An O-ring seal, including two or more O-rings 70, is provided between an outer surface of each respective adapter portion 66 and an inner circumference of a respective socket 68. For this purpose, the tubular adapter portion 66 may be provided with circumferential indentations, as shown herein, into which the O-rings 70 may fit, or the socket 68 may be provided with radially inwardly extending ledges for locating the O-rings therebetween. The innermost surface of the tubular socket 68 and the outermost surface of the tubular adapter portion 66 fit closely against one another, and the O-rings 70 prevent any leaks between the two. The receiver cup 50 can be snapped together with the socket 68 by way of locking tabs (an upper one of which is shown at 55) extending above and below the adapter portion 66. Locking tabs 55 fit into upper and lower tab receiver slots 57 situated in the upper and lower walls of the socket 68. Each locking tab 55 has a ramped protrusion 61 on its distal end, the ramping of which allows the locking tab 55 to slide into and through a respective receiver slot 57 with relative ease. When the protrusions 61 spring out of the opposite ends of the receiver slots 57, they act as positive stops that prevent the receiver cup 50 from falling out of the socket 68. After the adapter portion 66 has been inserted and locked into the socket 68, the receiver cup 50 may be further fastened to the fuel rail 28 by way of a fastener 81, which may extend through a tab 83 on the receiver cup 50 and into a fastener receiver 84 that protrudes from the side of the fuel rail 28. In other examples, these parts may be friction fit, adhered, or otherwise fastened to one another.
(19) Each socket 68 includes a transition passage 72 that connects a central passage 74 of the fuel rail 28 to a respective connector passage 52 of a respective receiver cup 50. A center axis 76 of the transition passage 72 is oriented perpendicular to the center axis 30 of the fuel rail 28 and perpendicular to the center axis 54 of the connector passage 52. For example, referring to
(20) Thus, the flow of fuel through the fuel delivery system 33 can be described as follows. Fuel flows from the fuel pump 36 through the central passage 74 of the fuel rail 28 in a first direction, next turns at a right angle to flow through each respective transition passage 72, next turns at a right angle to flow in a second direction through each respective connector passage 52, and next turns at an angle of less than 180 degrees to flow in a third direction through each respective fuel injector 48. More generally, fuel flows from the fuel pump 36 through the fuel rail 28 in the first direction, next turns at a right angle and flows in at least a second direction through each respective connector passage 52, and next turns at the angle of less than 180 degrees to flow in the third direction through each respective fuel injector 48. In one example, fuel flows away from the engine 12 after exiting the fuel rail 28 (such as through transition passage 72), and before flowing in the third direction toward the engine 12 (such as through fuel injector 48).
(21) Fuel is then injected into the intake passage 38 with which the fuel injector 48 is associated and is thereafter sucked as part of a fuel-air mixture into the cylinder 20 upon opening of the intake valve. According to the present disclosure, the first direction (of the central passage 74 along center axis 30) is vertical. The second direction (of the connector passage 52 along center axis 54) is horizontal. The third direction (of center axis 58 of fuel injector 48) is also horizontal. Additionally, in the present example, each of the first, second, and third directions is perpendicular to the other of the first, second, and third directions. More generally, the first direction may be vertical and the second and third directions may be horizontal. The direction of center axis 76 of transition passage 72 may also be horizontal, and may be perpendicular to the center axis 30 of the fuel rail 28 and perpendicular to the axis 54 of the connector passage 52. In the example shown, the center axis 76 of the transition passage 72 is parallel to and offset from the center axis 58 of the fuel injector 48. In the present example, the rail center axis 30 does not intersect with the injector center axes 58 and does not intersect with respective port center axes 54 of the ports 65 in the body portions 60 of the receiver cups 50.
(22) The layout of the components of the fuel delivery system 33 with respect to one another, coupled with the fact that the vertical center axis 30 of the fuel rail 28 does not intersect with the horizontal center axes 54 of the connector passages 52 (nor with the with the center axes of 54 the ports 65 in the body portions 60 of the receiver cups 50), ensures that the fuel delivery system 33 has a low profile and is tucked in closely to the engine 12. This means that the fuel rail 28 can be eliminated as a determining factor for how close the cowl 14 can be placed to an outer surface of the engine 12. For example, referring to
(23) Some specific distances are included below in order to describe the relationship of the fuel delivery system components to the cylinder 20, cylinder head 16, and intake valve. For example, referring to
(24) Thus, as a result of the specific geometry, components, and layout of the above-mentioned fuel delivery system 33, the problem of spatial integration of a fuel rail assembly including a fuel rail volume, fuel injectors, electrical connectors, and associating mounting hardware and interfaces, either into and/or between base engine components, peripheral components, and cowl components can be solved. While a given distance needs to remain between the nozzle end 59 of the fuel injector 48 and the face 47 of the intake valve in order to provide enough distance for the fuel to mix with the intake air before entering the cylinder 20, the distance D provided herein has been tested and proves to be sufficient for good fuel economy and acceptable emissions. Although the electrical connector within the fuel injector 48 provides a limiting factor on how compact the fuel delivery system can be, and although a certain spacing may need to be provided between the outer surface 82 of the closed end 64 of the receiver cup 50 and the inner surface 32 of the cowl 14, the present geometry and layout allow the fuel rail 28 and associated components to be tucked within a space between the intake runner 24 and the cylinder head cover 80 while meeting these requirements. A design in which the center axis 30 of the fuel rail 28 is closer to the cylinder block 18 than are the center axes 54 of the connector passages 52, and in which fuel navigates the 90 turns described herein above, can allow for the fuel rail 28 to be installed with a low profile with respect to the engine 12.
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(27) According to yet another example of the present disclosure, with reference back to
(28) According to another example of the present disclosure, with reference now also to
(29) In the above description, certain terms have been used for brevity, clarity, and understanding. No unnecessary limitations are to be inferred therefrom beyond the requirement of the prior art because such terms are used for descriptive purposes and are intended to be broadly construed. The different systems described herein may be used alone or in combination with other systems. It is to be expected that various equivalents, alternatives and modifications are possible within the scope of the appended claims.