Patent Application
20130047963
The invention relates to fuel systems of internal combustion engines for vehicles and, more particularly, a method and system to detect unwanted and unwarranted chemical compounds in consumer loaded fuels.
Currently, there is no system in place, other than related impacted fault codes in the Engine Condition Monitoring (ECM) as required with the on-board diagnostic (OBD) systems, to note prior presence of adverse chemical compounds within the fuel system of a vehicle. Including the retrospective attempt to forensically demonstrate from causal testing or analysis of any deposits on components, it is very difficult for suppliers or the original equipment manufacturer (OEM) as a warranty provider to the retail customer, to prove a “conditions of use” violation that relieves the supplier and/or OEM of any warranty repair cost.
Proof of unauthorized substances in fuel are today derived from forensic testing on the components involved, typically long after the repairs have been done on the consumer's vehicle or after the OEM relation with the supplier has been substantially degraded. There is substantial lag time for such forensic testing and once completed, there is no definitive proof that the customer used a disallowed fuel.
Thus, there is a need to detect unwarranted chemical compounds in consumer loaded fuels via methods that are obvious and visual to dealer service personnel in a tamper resistant manner.
An object of the invention is to fulfill the need referred to above. In accordance with the principles of the present invention, this objective is obtained by providing a fuel supply system for a vehicle including a fuel tank for holding fuel therein, the fuel tank having a filler neck; a pump for pumping fuel from the tank; a filter for filtering fuel; a fuel rail for receiving filtered fuel originating from the pump; a pressure regulator for controlling pressure of fuel received by the fuel rail; and fuel injectors for injecting fuel, received from the fuel rail, into an internal combustion engine. The filler neck, tank, pump, filter, pressure regulator, and fuel rail are fluidly connected to define fuel flow path structure between the tank and the fuel injectors. A fuel detection system is in fluid communication with the fuel flow path structure. The fuel detection system includes a plurality of detectors. Each detector is constructed and arranged to be exposed to fuel to detect a distinct chemical element or compound in the fuel.
In accordance with another aspect of a disclosed embodiment, a method of detecting distinct chemical elements or compounds in fuel in a fuel supply system provides a fuel supply system of a vehicle to supply fuel from a fuel tank to a fuel rail, with the fuel rail feeding fuel injectors with fuel. The method provides a fuel detection system in the fuel supply system so as to be exposed to fuel to detect distinct chemical elements or compounds in the fuel.
Other objects, features and characteristics of the present invention, as well as the methods of operation and the functions of the related elements of the structure, the combination of parts and economics of manufacture will become more apparent upon consideration of the following detailed description and appended claims with reference to the accompanying drawings, all of which form a part of this specification.
The invention will be better understood from the following detailed description of the preferred embodiments thereof, taken in conjunction with the accompanying drawings, wherein like reference numerals refer to like parts, in which:
The embodiment provides a system and method to detect unwanted and unwarranted chemical compounds in consumer loaded fuels. The system protects the OEM and/or supplier from consumer attempts to disguise major engine damage caused by use of unauthorized fuel.
In accordance with an embodiment, a fuel detection system is shown, generally indicated at 28, in fluid communication with the fuel flow path structure 26. In the embodiment, the fuel detection system 28 is shown fluidly coupled with the fuel rail 20 for ease of access thereto. However, the fuel detection system 28 can be coupled anywhere within the fuel flow path structure 26 such as on the fuel pump 14, the filter 16, the regulator 18, so long that it is exposed to fuel. The fuel detection system 28′ can be provided in the filler neck 13, with a transparent window alerting the operator to a fueling violation, especially for fleet vehicles.
The fuel detection system 28 includes a plurality of chemical element or chemical compound detectors 30, 30′, 30″, 30′″, etc. that are exposed to fuel to detect parts per million (ppm) of specific chemical elements or compounds in the fuel. Compounds of interest that have existing test methods available include, but are not limited to, ethanol, methanol, water, sulfides, etc. These compounds impact the life of the fuel injectors, and other fuel system components, by low lubricity, aggressive attack, corrosion, and deposit formation. Thus, for example, detector 30 can be configured to detect ethanol, detector 30′ can be configured to detect methanol, detector 30″ can be configured to detect water or water vapor, and detector 30′″ can be configured to detect sulfides. The detectors 30, 30′, 30″, 30′″ can be in the form of detector tubes manufactured by Gastec Corporation of Fukaya, Ayase-City, Japan (such as Model No. 6, No. 111L, No. 112L). Alternatively, the detectors 30, 30′, 30″, 30′″ can be dehydrogenase-based biosensors, bioassay tests, strips, or chemical-optical kits. To detect sulfide, a conventional sulfide-selective optode membrane can be used.
Such detectors offer the possibility of permanent change, not erasable by subsequent lack of continued exposure, or by human intervention short of replacing the entire detection system 28. The detectors 30, 30′, 30″, 30′″ can detect varying levels of ppm of distinct chemical compounds/elements.
The increasing interest in bio fuels, typically utilized in given and limited concentrations within conventional gasoline or diesel fuel, as well as emerging country markets, leave open the real and documented possibilities of consumers utilizing higher percentages of bio additives in fuels than what their vehicles are certified to. This may also occur without the consumer's awareness at unbranded, low control, retail fueling stations. The belief that government regulations protect the integrity of the retail fuel supply ignores proven violations in developing countries, as well as the developed countries. There is potential of consumers using brewed bio fuels, as well as the fact that vehicles remain unprotected from their owner's misuse of fuels since there is no dedicated fueling nozzle configuration per fuel composition (excluding leaded vs. non-leaded fuel, since separate nozzle configurations are provided for these fuels). While OBDs might indicate a fault light if the offending chemical imbalance is detected, these codes are typically suggestive and not definitive, as well as erasable by elimination of 12 V power to the ECM. Further, the reliance of most OBD systems on inductance, conductivity, or capacitance, ignores the possibility of changes, or lack thereof, in these parameters caused by varying fuel components or contaminants that may have markedly differing impacts on the operation or material of supplied device components used in the fuel systems. An example of this is identical pH leading to identical conductivity readings of given concentrations of acetic acid, vs. hydrochloric acid, vs. sulfuric acid. These three acids differ markedly in their attack on metals, and are documented to exist in varying quantities in both bio and regular fuels from various countries, depending on the local fuel processing used.
A given diffusion rate of the tested fuel stream across the reactive media of the detector 30 may be needed. Such cases would require a labyrinth or orifice built within fuel rail 20, regulator 18 or other supplied fuel system components in order to achieve the required diffusion rate.
The fuel detection system 28 can be an integral member in the fuel flow path structure 26 such as being integral with the fuel rail 20 as noted above, or can be an add-on member. Thus, an aftermarket add-on detection system 28 is possible in a package design that can be retrofitted to any vehicle, or applied as a new OEM accessory. Packaging of multiple detectors 30, each specific to a given chemical compound, can also be accomplished in a single unit by modular slotting, similar to either health care industry blood or other specimen testing or personal computer assembly where purchase specified requirements can be simply added via modules into a series of available slots or cubes. In this manner, even though a given vehicle may be produced in a single country, its use might become country specific, and a vehicle selected for export might be given a different detector set than a domestic unit.
The fuel detection system 28 or 28′ provides an easy and effective way for vehicle service personnel to determine if improper fuel was used by the vehicle's operator and thus, determine if the vehicle warranty was violated. The service personnel could merely access the detection system 28 or 28′ and inspect the detectors 30, 30′, etc., for the presence of any chemical element or compound detected that should not be present in the fuel system. The detection system 28 or 28′ is completely passive, with no sampling, active analysis, processing, electrical current, etc. required.
With the system 28, 28′, there is no data loss with the loss of 12 V power, and there is no data loss with fuel change over, post any incident. Further, depending on the customer, country, and economic cycles, circumstances may easily result in fuel aging in a given vehicle. This aging period is easily measured in weeks, which is the same time span that a given batch of fuel exists in the United States prior to complete consumption of that market batch. Still further, corrections to low pH in fuel stocks, while easily accomplished by sodium bicarbonate, result in dramatically increased fuel conductivity, with resultant galvanic corrosion of fuel system components. As a result, an insult to fuel system components may be due to attempts to mitigate the primary deficiency of the fuel. This system of multiple detectors enhances the ability to identify possible vehicle owner interaction with the vehicle fuel, and/or adulteration by the retail fuel dealer, by logging multiple insults. Further, by adding a “dead end” spur, with an additional set of multiple detectors, to the fuel line via a “T” fitting, it is also possible to calculate the approximate timing of multiple insults by means of the probable diffusion time of the insult through the distance of the static fuel in the length of the spur line. Likewise there are embodiments and variations possible by use of multiple detector sets and tie- ins to the vehicle ECM to perform additional functions, such as driver notification via the instrument panel, dealer notification of OBD fault codes, termination of engine function to avoid further damage, identification of subsequent insult events by means of alternative parallel fuel paths with detector sets, etc. In the case of General Motor's Onstar, it would also be possible to download fuel information to the Onstar center. It is noted that embodiments that include visibility of the data to other than dealer maintenance personnel are contrary to a tamper proof benefit, but these can be constructed in such a manner, should it be desirable, to include hurdles to tampering, or the benefits of visibility may be seen to out-way the loss of tamper proofing.
The foregoing preferred embodiments have been shown and described for the purposes of illustrating the structural and functional principles of the present invention, as well as illustrating the methods of employing the preferred embodiments and are subject to change without departing from such principles. Therefore, this invention includes all modifications encompassed within the spirit of the following claims.
