The invention relates to engine technology, and more particularly to fuel rails and wiring harness management assemblies for Electronic Fuel Injection of the Distributorless Ignition System (DIS) type, comprising a multi-planar elongated plate having a depending mid-rib that is bored for fuel supply along a bank of cylinders of an internal combustion engine, and which includes spaced bores along the mid-rib that engage and supply fuel to fuel injectors. In addition, the plate flanges flanking the rib function to shield wiring harness leads to the EFI injectors of the engine.
Over the past 50 years of automotive engineering, fuel injection has become the dominant system for mixing fuel with air for combusition in the engine cylinders. Early systems in the mid-1950's were mechanical in nature, but were supplanted in the 1960's and 1970's with various types of Electronic Fuel Injection, in large part due to the ability of EFIs to better achieve stoichiometric engine operation which reduced engine pollution. The closed loop systems introduced in the 80's improved the air/fuel mixture control by feed-back from an oxygen sensor located in the engine exhaust. Since that time, EFIs have continued to evolve and become more reliable, and except where there are no strict emission regulations, carburetor-controlled engines are the exception.
The fuel injector dispenses fuel directly into the engine air stream, typically being located in a port a few inches upstream of the intake valve of each cylinder, or directly into the cylinder itself. While the direct injection approach was initially used for diesel engines, gasoline engines now use direct injection. Typically, injectors employ a solenoid that is normally closed, that is a tapered tip of a solenoid plunger seats against a conical valve seat. The injectors are wired to an EFI control system microprocessor, and plumbed to the fuel lines. When the solenoid is energized by a signal from the EFI/DIS controller, the plunger is retracted and fuel under pressure is injected, passing through the valve seat and through an atomizer nozzle, thereby spraying fuel into the air stream passing through the port, or spraying fuel directly into the combustion chamber portion of the cylinder. In turn, the injector is connected to a high pressure fuel line, 40-50 psi for port fuel injection and 200-250 psi for direct injection. At these pressures, the fuel lines must be much more robust than the very low pressure that had been used for venturi-fed carburetor systems. This requirement led to the introduction of “fuel rails”, rigid pipes connected to a high pressure fuel line coming from the fuel tank via the high pressure fuel pump. The fuel rails are plumbed to the injectors.
Current fuel rails comprise simple exposed pipes or conduits that are cantilevered above the cylinder banks of the IC engine to which they are installed. For a V8 engine, two rails are provided, one for each bank of cylinders. They include a cross-over pipe that joins the fuel rails medially of their ends, and the inlet high pressure fuel line feeds into the cross-over pipe.
Thus, the current fuel rail design is an “H”-shape as seen in plan view from above, each of the long, vertical members representing a rail for one of the two cylinder banks, and the cross-bar representing the cross-over pipe. The fuel from the fuel pump feeds into the center of the cross-bar of the “H”-shaped design. This “H” design routes the fuel over the engine, thus presenting service technicians with a line that can be in the way of other work, and if snagged, can result in breakage of seals with attendant leakage of fuel. In addition, there is little if any flex in the cross-over pipe, so the current assembly has to be aligned with, in a V8 engine, eight spaced injectors or injector ports in both cylinder heads simultaneously, a task that is not easy.
The current type of fuel rail assembly is secured to the engine only via the injectors; that is, the injectors themselves serve as the support pillars. Bumping the rails can break the injector seals causing dangerous fuel leaks on hot engine parts during operation, in part because the rails are of low mass, and do not have sufficient inertia to absorb a bump or jostle. The net result is that the rails, the fuel line, the cross-over pipe, and the wiring from the EFI/DIS controller(s) and power supply to the injectors can come into contact with various other engine parts, and present complex, overlapping parts that must be properly routed and carefully kept clear-of during servicing.
In addition to the wiring currently being essentially loose and exposed, the insulation and its support or retainer brackets on the inner surface of the hood can come into contact with the wiring when the hood is closed, pressing down on the wiring. This can lead to two problems: First, rubbing wear on the wiring that can cause breaks or change in conductive properties of the wiring; Second, there is a potential for pressing the wiring down onto hot surfaces of the engine below the wiring. In addition, exposed wiring can become snagged during servicing.
Accordingly, there is an unmet need in the art for an assembly that protects wiring and better routes fuel lines while at the same time is robust, more massive, and attractive.
The invention relates to a robust, extruded, cast or billet-type combined fuel rail and wiring harness shield assembly for a bank of cylinders of an IC engine having a Distributorless Ignition System and an Electronic Fuel Injection system. The inventive fuel rail/harness shield assembly comprises a rectangular multi-planar plate having an integral longitudinal mid-rib depending from one side that is bored both longitudinally and from below to form a fuel distribution manifold to the EFI injectors mounted in, and spaced along, the underside of the rib. In cross-section, the assembly is generally T-shaped, and is preferably constructed of aluminum extruded in the cross-sectional shape. The rectangular plate may be generally described as “wings” extending laterally from the top of the mid-rib.
The fuel rail mid-rib provides a continuous web of material between the spaced, adjacent injector mounting bores that are precision-milled at the appropriate angle, into the rib from below. This continuous mid-rib web serves to reinforce the injector mounting, making the injectors less susceptible to vibration during operation or damage during servicing. Stated another way, the injectors are mounted in the rib, rather than in the conventional assembly where the fuel rail (tube) is mounted on the injectors. The result is that the combination of the inventive fuel rail and injectors forms a more massive, more rigid assembly that is near-monolithic, and thus can better withstand vibrations in operation and bumping and jostling during servicing.
The mid-rib, seen end-on in end elevation, is generally orthogonal with respect to the wing structure, but in a particular application, i.e., for a particular engine, is canted so that its vertical center line forms an included angle with respect to a side wing on the order of from about 70°-85°. In addition, the injector bores are also canted on the order of from about 5°-20° to match the injector angle into the port or cylinder, depending on the type of EFI system the particular engine employs (port or direct injection).
Flanking each side of the mid-rib are transversely extending wings that serve to shield and manage the wiring to the injectors or/and the coils, or other wiring that may be part of the overall engine wiring harness, e.g., including sensor wires to the Powertrain Control Module that controls the EFI and DIS systems. The two side wings are different, one side wing includes an angled, full length marginal flange, and the other side wing is relatively straight. The flange is angled down, that is, toward the underside of the plate on which the rib is disposed, the included angle being approximately 135°. As mounted on a V8 engine, for example, the angle between the cylinders is on the order of 90°, and the angled flange is disposed on the outboard side of the cylinder bank so that the flange points substantially vertically downwardly.
In addition to the flanges being robust to protect the wiring, and to prevent hood insulation or other parts pressing on the wiring, the mass of the inventive fuel rail/harness protection assembly provides cooling as the flange and wings provide heat radiating function. That is they serve as cooling fins.
The inventive fuel rail/harness protection assembly fuel bore is threaded at both ends. In a first, series fueling embodiment, the assembly includes an inlet fuel line, such as a flexible, braided stainless steel-covered high pressure plastic fuel line, threaded into a first end of a first rail. At the second end of the first embodiment, a flexible cross-over line is threaded. That cross-over line threads into the second end of a second inventive fuel rail/harness protection assembly, and the first end of the second assembly is plugged. In this first embodiment, the inlet fuel line is fed into the back, or bulk-head end of the inventive assembly, and the cross-over line is at the forward end of the engine. The in-feed can be at either the right side or the left side of the engine. Since there are two inventive assemblies used in the combination for a V8 engine, the alignment is simpler. In addition, simply by changing the length of the flexible crossover line at the front of the engine, the same inventive assemblies can be used for 60° V or 90° V engines. The rail can also be easily converted to V6 by cutting off the extra injector segment of the plate and re-threading the longitudinal bore of the fuel distribution manifold. Conversely, the fuel rail extrusion may be longer to accommodate V10 or V12 engines, having cylinder banks of 5 and 6 cylinders, respectively.
In the preferred, second, parallel fueling embodiment, both first ends of the inventive fuel rail assemblies are plugged. The inlet fuel line is Tee-d into the cross-over line so that fuel is fed to both of the inventive fuel rail assemblies, one on each bank, simultaneously. In this embodiment the inlet fuel line is Tee-d in at the forward end of the engine, although it may be introduced next to the bulkhead end of the engine.
The preferred embodiment of the inventive fuel rail module calls for the injectors to be inserted in, and firmly and tightly seated in, the angularly oriented, precision milled bores in the rib, which bores intersect the longitudinal fuel channel. The output end of the injectors are first press fit into threaded holes in the air input runners (ports) going to each cylinder, or in the case of direct injection, directly into the cylinder head injector ports. Optionally, injectors are threaded into the cylinder head or the air intake manifold branch runners. Then, an inventive fuel rail module is press fitted simultaneously onto the input shanks of the injectors of a bank of cylinders. The injectors include O-ring seals, and the bores closely match the size of the injector shank. The inlet aperture of the injector is thus connected with the longitudinal bore of the inventive fuel rail module permitting high pressure fuel conduction to the injectors. This method of seating provides a near-monolithic fuel rail/multiple injector assembly that has more inertial mass that can resist and dampen vibration and shocks.
In a first, preferred embodiment of the mounting system, 2 or 3 slotted holes are provided in one wing adjacent to, but not intersecting, the mid-rib. The inventive fuel rail assembly is then bolted to the OEM bosses provided either in the head or the air intake manifold. The slots are typically oriented parallel to the longitudinal axis of the mid-rib, and they permit whatever slight fore-aft orientation adjustment as may be needed for accurate mating of the inventive fuel rail assembly to the injectors.
As an alternative mounting system, the head of the cylinder block or the air intake manifold may be provided with one or more, typically 2 or 3, spaced, generally U-shaped clips. These clips have somewhat enlarged semi-circular profiles adjacent the tops of the clip arms, that closely fit the rib contour. This permits securing the inventive fuel rail simply by aligning the injector bores over the injectors and pushing down so that the clips tightly engage the rib as the injectors slide into the bores.
Still other advantages of the inventive assembly will be evident to those skilled in the art.
The invention is described in more detail with reference to the CAD drawings and photos, in which:
The following detailed description illustrates the invention by way of example, not by way of limitation of the scope, equivalents or principles of the invention. This description will clearly enable one skilled in the art to make and use the invention, and describes several embodiments, adaptations, variations, alternatives and uses of the invention, including what is presently believed to be the best modes of carrying out the invention.
In this regard, the invention is illustrated in the several figures, and is of sufficient complexity that the many parts, interrelationships, and sub-combinations thereof simply cannot be fully illustrated in a single patent-type drawing. For clarity and conciseness, several of the drawings show in schematic, or omit, parts that are not essential in that drawing to a description of a particular feature, aspect or principle of the invention being disclosed. Thus, the best mode embodiment of one feature may be shown in one drawing, and the best mode of another feature will be called out in another drawing.
The top plate extensions that project laterally on each side of the rib form first and second “wings” 20 and 22, respectively, which lie in a common plane. At least one wing, here wing 22, includes a flange 24 that is angled down at about a 45° angle from the wings 20 and 22. As best seen in
One skilled in the art will appreciate that to further assist in wiring management, the underside of the wings 20, 22 and 24 may be fitted with one or more wiring bundle routing clips 64a, 64b, 64c, best seen in
One skilled in the art will recognize that depending on engine orientation and clearance in the engine bay, the routing can be reversed, either side to side or front to back, as needed. In addition, in the preferred example shown in
The lower half of
This figure also shows the conventional fuel rail assembly is H-shaped in plan view, with the cross-over rigid pipe connecting the two rails at the fore-aft mid-point of the engine, and hindering lift-off/place-down access to the air intake manifold. In contrast, using the inventive assembly, the air intake manifold is not obstructed at its midpoint. It is also evident from this figure that when the passenger side inventive fuel rail assembly is used to replace the conventional fuel rail 54, the wiring bundles 60a, and 61 would be covered by the wings 20, 22 and flange 24. This is evident by noting the wiring bundle 60b is shielded by the wing in the foreground.
Although the mass of the inventive assembly, press fit onto from 3-6 injectors per bank (depending on the number of engine cylinders), helps to retain the inventive assembly in place, it is preferred to include brackets or screws for securing it to the head or the air manifold. Thus, one or more snap-in-place type friction bracket can be screwed to the head, as shown in
In addition, the robust wing and rib construction of the inventive fuel rail resists puncturing, far better than the relatively thinner tubes currently in use, and permits a wider range of fuel pressures to be used, particularly in supercharged and diesel engines. Thus the inventive fuel rail system is useful for gasoline, diesel, bio-diesel, alcohol-containing and racing fuels at higher pressures, above about 200 psi, than for pump gas.
Accordingly, the inventive fuel rail and wiring harness management assembly is characterized as an assembly for internal combustion engines having a pressurized electronic fuel injection system comprising: a planar plate, elongated in a first, longitudinal length, and having a pair of opposed, laterally extending wings, each of said wings has an exterior marginal edge, said wing edges being generally parallel to each other; at least one of the wings includes a flange extending at an angle downwardly relative to the plane of said plate; a rib projecting downwardly from the underside of the plate, the rib being disposed generally medially between the wing marginal edges and having a bottom surface spaced downwardly from the planar plate; the rib extends the longitudinal length of the plate and includes a longitudinal bore extending the length of the rib from a first, proximal end to a second, distal end, functioning as a fuel distribution manifold for supply of fuel under pressure to fuel injectors of the engine; the rib includes a plurality of bores extending from the rib bottom surface and intersecting the longitudinal fuel supply bore, the intersecting bores being sized for fuel injectors for the engine and disposed medial of the rib ends; and the flange, wing and rib defining at least one channel for routing and managing wiring associated with the injectors of the engine or ignition wires for the cylinders of the engine.
It is clear that the inventive fuel rail/wiring harness protector assembly, including fuel lines, injectors, end plug, an option clips, of this application has wide applicability to the engine field, and more particularly to the automotive industry. The system clearly provides advantages for fuel routing and wiring management. Thus, the inventive assembly has the clear potential of becoming adopted as the new standard for apparatus and methods of fuel delivery and wiring protection.
It should be understood that various modifications within the scope of this invention can be made by one of ordinary skill in the art without departing from the spirit thereof and without undue experimentation. For example, the wings and flange can have a wide range of designs to provide the functionalities disclosed herein. Likewise the fuel delivery rib may be sized to any particular engine, and the mode of securing the assembly to the head may include any convenient attachment mode(s) including clips, screws, bolts, flanges and brackets. The flange size, angle, and marginal shape may be varied to provide whatever amount of coverage and clearances may be needed for a particular engine. In addition, clips to retain wires in the wiring channel(s) may be provided for better management of wiring to maintain the wiring clear of other engine parts. The cross-over line, although preferred to be flexible, may be rigid pipe. This invention is therefore to be defined by the scope of the appended claims as broadly as the prior art will permit, and in view of the specification if need be, including a full range of current and future equivalents thereof.
This application is the US Regular Application corresponding to U.S. Provisional Application by the same inventor filed under the same title on Oct. 29, 2007 as U.S. Ser. No. 60/983,346, the benefit of the filing date of which is hereby claimed under 35 US Code §§119, 120, ff, and the text and Figures of which are hereby incorporated by reference to the extent needed for support under 35 US Code §112.
Number | Name | Date | Kind |
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6817337 | Siring et al. | Nov 2004 | B1 |
Number | Date | Country | |
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60983346 | Oct 2007 | US |