Patent Publication Number: US-2022235730-A1

Title: Fuel injector interface device and method of use

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a Continuation-in-Part of U.S. application Ser. No. 16/813,187 filed on Mar. 9, 2020, the contents of each of which are incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present invention relates generally to automotive diagnostic tools, and more particularly to an interface device for detecting anomalies in fuel injectors. 
     BACKGROUND 
     The statements in this section merely provide background information related to the present disclosure and may not constitute prior art. 
     Since 2008, most automobile manufacturers have switched from standard multi-port fuel injection systems to gasoline direct injection systems which are much more fuel efficient, produce higher power, and have lower emission rates. However, this change has resulted in a higher instance of fuel system problems than the previous system. 
     Although some manufacturers have designed their systems with functionality for troubleshooting individual cylinders and injectors, many have not. As a result, when fuel-related problems arise, the standard technical protocol is to remove all injectors from the engine and have them sent to a facility for individual bench testing and/or cleaning to determine which injector is malfunctioning. 
     Such a process is extremely expensive and time consuming for the vehicle owner who must be without their vehicle for several days in such situations. 
     Accordingly, it would be beneficial to provide a device that can interface with all fuel injectors of an automobile to allow a technician to quickly and easily test the functionality of the same without the drawbacks described above. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to a fuel injector interface device and associated method of using the same. 
     One embodiment of the present invention can include an interface device having a plurality of input leads and a plurality of output leads. The input leads can be communicatively linked to a vehicle fuel injection system, and preferably to the fuel pressure sensor along the common rail. The output leads can be communicatively linked with a display device such as a diagnostic scope, for example. 
     Circuitry positioned within the interface device can detect the rail pressure signals and output data to the display device representing a graphical depiction of the same. Each of these signals can be mapped to an individual fuel injector of an engine cylinder and fluctuations in the strength of the displayed signals can represent anomalies in a particular fuel injector. 
     This summary is provided merely to introduce certain concepts and not to identify key or essential features of the claimed subject matter. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Presently preferred embodiments are shown in the drawings. It should be appreciated, however, that the invention is not limited to the precise arrangements and instrumentalities shown. 
         FIG. 1  is perspective view of an exemplary fuel injector interface device in operation, in accordance with one embodiment of the invention. 
         FIG. 2  is a simplified block diagram of the internal components of the exemplary fuel injector interface device, in accordance with one embodiment of the invention. 
         FIG. 3  is a flow diagram of a method for using the exemplary fuel injector interface device to detect an anomaly in a fuel injector, in accordance with one embodiment of the invention. 
         FIG. 4  is a graph depicting a normal fuel injector performance, in accordance with one embodiment of the invention. 
         FIG. 5  is a graph depicting a faulty fuel injector, in accordance with one embodiment of the invention. 
         FIG. 6  is another perspective view of an exemplary fuel injector interface device in operation, in accordance with one embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     While the specification concludes with claims defining the features of the invention that are regarded as novel, it is believed that the invention will be better understood from a consideration of the description in conjunction with the drawings. As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention which can be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the inventive arrangements in virtually any appropriately detailed structure. Further, the terms and phrases used herein are not intended to be limiting, but rather to provide an understandable description of the invention. 
     Definitions 
     As described herein, a “unit” means a series of identified physical components and/or functionally equivalent components which are linked together and/or function together to perform a specified function. 
     As described herein, the term “removably secured,” and derivatives thereof shall be used to describe a situation wherein two or more objects are joined together in a non-permanent manner so as to allow the same objects to be repeatedly joined and separated. 
       FIGS. 1-5  illustrate one embodiment of a fuel injector interface device  10  and corresponding method that are useful for understanding the inventive concepts disclosed herein. In each of the drawings, identical reference numerals are used for like elements of the invention or elements of like function. For the sake of clarity, only those reference numerals are shown in the individual figures which are necessary for the description of the respective figure. For purposes of this description, the terms “upper,” “bottom,” “right,” “left,” “front,” “vertical,” “horizontal,” and derivatives thereof shall relate to the invention as oriented in  FIG. 1 . 
     Although described herein as a device for detecting anomalies within a fuel injection system, the inventive concepts are not so limiting. To this end, those of skill in the art will recognize that the functionality of the inventive device may be used for many other purposes where it is useful to sense voltages and/or “zoom in” on virtually any automotive signal. In this regard, the inventive device can function to reject non-automotive frequency signals by filtering out signals less than 2 HZ and filtering signals greater than about 900 HZ and by amplifying the leftover. Accordingly, the application is not to be construed as limiting to any particular use or purpose. 
     In direct injection gasoline systems, a common fuel rail  1  is positioned between a fuel pump  2  and a plurality of fuel injectors I 1 , I 2 , I 3  and I 4 —in the case of a four-cylinder engine. A fuel pressure sensor  4  is positioned along the fuel rail and is communicatively linked to the vehicle&#39;s onboard computer and is powered by the onboard vehicle battery. In vehicles produced before 2017, the fuel pressure sensor  4  outputted an analog signal whereas vehicles produced after 2017 outputted a digital signal. Each of the injectors I 1 -I 4  are also communicatively linked  5  with an onboard controller. Although not illustrated, six-cylinder and eight-cylinder engines will have six and eight fuel injectors, respectively, and the functionality described herein will be the same. 
     As will be described below, the inventive fuel injector interface device  10  includes functionality for detecting and monitoring fluctuations in the common rail  1 , as detected by the pressure sensor  4  during engine operation. The system also includes functionality for outputting a graphical illustration of the filtered rail pressure signal on an integrated display and/or a separate display unit  6  such as a mechanic&#39;s diagnostic scope, for example, so as to allow a technician to visually detect anomalies in the performance of an individual fuel injector I 1 -I 4 . 
     As shown at  FIG. 1 , one embodiment of the interface device  10  can include a main body  11 , input leads  12  and  13 , output leads  14  and  15 , and an internal controller/circuitry  20 . The main body  11  can include any number of different shapes and sizes and can be constructed from any number of different materials suitable for encompassing each of the internal elements. In one preferred embodiment, the main body  11  can be constructed from extruded aluminum, and/or lightweight injection molded plastic having a plurality of internal connectors (not shown) for securely housing and positioning each of the device elements. Of course, any number of other known construction materials such as PVC, metals and composites, for example, are also contemplated. Each of the leads  12 - 15  can include any type of materials suitable for transmitting electronic signals. Each of the leads can also include connectors/adaptors along the ends so as to mate with or connect to a secondary device. These connectors can include, for example, various shaft-type plug connectors (e.g., banana plug), and/or compression fittings such as alligator clips, for example. 
     As shown in the block diagram of  FIG. 2 , the internal circuitry  20  of the device  10  can include one or more components such as the illustrated power source  21 , switch  22   a , light  22   b , boost converter  23 , power conditioner  24 , an input buffer/decoupler  25 , a high pass filter  26 , a low pass filter  27 , an output signal amplifier  28 , and a programmable micro controller  29 . 
     Although illustrated as separate elements, those of skill in the art will recognize that one or more system components may comprise or include one or more printed circuit boards (PCB) containing any number of integrated circuit or circuits for completing the activities described herein. Of course, any number of other analog and/or digital components capable of performing the below described functionality can be provided in place of, or in conjunction with the below described controller elements. 
     The power source  21  can include any number and type of devices capable of providing the base power requirements to the internal circuitry. In the preferred embodiment, the power source can include a 9-volt battery, for example, however other types and voltages are also contemplated. 
     The switch  22   a  can be connected to the power source and can function to allow a user to power the device between an ON and OFF operating state. Likewise, an optional LED light  22   b  can provide a visual indication that the device  10  is in the ON position. 
     The boost converter  23  can be communicatively linked to the power source and can function to increase the voltage supplied therefrom. In the preferred embodiment, the boost converter can include, comprise or consist of circuitry capable of boosting 9 volts supplied by the power source to an output of 32 volts; however, any number of other devices and voltages are also contemplated. 
     The power conditioner  24  can be communicatively linked to the boost converter and can function to establish a floating ground/reference low for the Op Amps to work from. 
     The input buffer and decoupler  25  can be communicatively linked to the input leads  12  and  13 , which are in turn connected to the low reference/ground pin and the positive pin at the vehicle pressure sensor  4 , respectively. 
     In vehicles with analog pressure sensors  4 , the decoupler  25  can pass the received low reference signal from lead  12  to the ground output lead  14  and can pass the received pressure sensor signal from lead  13  directly to the high pass filter  26 . Conversely, if the pressure sensor  4  outputs a digital signal, as is common for vehicles produced after 2017, the decoupler  25  can pass the received low reference signal from lead  12  to the ground output lead  14  and can pass the received pressure sensor signal from lead  13  to the programmable micro controller  29 . 
     The programmable micro controller  29  can be communicatively linked to the output of the decoupler  25  and can include programmatic instructions to enable the processor to decode the digital signal from the pressure sensor  4 . Upon decoding the signal, the programmable micro controller can convert the signal to an analog output signal that is proportional to the binary input signal. This analog output signal can then be sent directly to the high pass filter  26 . 
     The integrating active high pass filter  26  can be communicatively linked to the output of the decoupler  25  and the output of the programmable micro controller  29 , and can function to cancel the DC offset from the received pressure sensor signal and to establish a high pass frequency cutoff. Rather than using a standard resistor/capacitor setup which places a capacitor directly in the input signal path, thus causing distortion issues, the high pass filter described herein directly receives the input signal, thus giving a better reproduction of the signal while still canceling out the dc offset. 
     The low pass filter  27  can be communicatively linked to both the active high pass filter  26  and the power conditioner  24  and can function to remove any high frequency noise from the received signals. In the preferred embodiment, the filter will preferably comprise a 6 th  order low pass filter which provides a 36 db per octave attenuation, thus reducing the signal noise rapidly as frequencies exceed the cutoff frequency and allowing for significantly less distortion in the input signal. 
     The output signal amplifier  28  can amplify the received signals from the low pass filter  27  and send the amplified signal to the output lead  15 . The output amplifier can also receive an arbitrary analog signal from the microcontroller and can superimpose the signal onto the final output signal for testing of digital sensors. 
     In one embodiment, output leads  14  and  15  can be connected to various types of external display devices  6  that are capable of receiving electrical signals and displaying the same in a visual manner such as a graph, for example. In one embodiment, the display  6  can include, comprise or consist of an automotive mechanic diagnostic tablet, such as the Verus Edge Automotive Diagnostic and Information Tool having an onboard scope module that is commercially available from SNAP-ON, for example. Of course, any number of other types of display devices are also contemplated. 
     A method  300  of connecting the interface device  10  will now be described with reference to  FIG. 3 . As shown, the method can begin at step  305  where the input leads  12  and  13  are connected to the vehicle ground/low reference and fuel pressure sensor  4 , respectively. Next, the output leads  14  and  15  can be connected to the negative and positive scope input leads on a suitable display unit  6  at step  310 . 
     Next, the method can proceed to step  315  where an auxiliary lead  7  from the scope  6  can be connected to the control line  5  for a particular fuel injector I 1 -I 4 . In the preferred embodiment, the lead will be connected to the first injector so as to clearly identify the firing order of the injectors on the display. 
     Next, both the device  10  and the scope  6  can be powered on and the vehicle engine can be started at step  320 , and a graphical representation of the fuel injector performances can be shown on the display  6 , at step  325 . 
     Finally, at step  330 , a user can view the graph on the display  6  to determine anomalies in individual fuel injector performance. 
       FIG. 4  shows an exemplary waveform representation of fuel injector performance on a display  6  that is connected to the device  10  as described above. In the present embodiment, line  410  represents the signal that is received by the auxiliary lead  7  which is preferably connected to the fuel injector control line of the first cylinder&#39;s fuel injector IL Likewise, line  420  represents the signal received by input lead  13  that is connected to the pressure sensor  4  of the vehicle. 
     As shown, the control line  410  shows a signal spike  411  each time the first injector I 1  fires. Because line  410  spikes each time injector I 1  fires, the technician can easily and visually correlate the corresponding spikes along line  420  to each of the fuel injectors. As such, line  420  has a series of evenly spaced spikes  421 ,  422 ,  423 , and  424 , representing the filtered rail pressure signals for each of the four individual injectors I 1 , I 2 , I 3  and I 4  of the four-cylinder engine. 
     In the present embodiment shown at  FIG. 4 , the spikes  421 - 424  of line  420  are uniform with each other during engine operation. Such a situation provides a clear visual indicator that each injector I 1 -I 4  is firing properly and proportionally to the other injectors in the engine. As such, the graph of  FIG. 4  indicates the fuel injectors of the target vehicle are operating correctly. 
       FIG. 5  illustrates another exemplary waveform representation of fuel injector performance on a display  6  that is connected to the device  10  as described above. 
     As shown, the spikes of line  420  in  FIG. 5  are not uniform as the signal  422  representing the second injector I 2  is well beyond what the other injectors are reporting. As such, the graph of  FIG. 5  indicates that the second injector I 2  is faulty and needs to be replaced. 
     Although described above as utilizing an externally located display  6 , other embodiments are contemplated wherein the device  10  can include a dedicated display and input components. To this end,  FIG. 6  illustrates one embodiment of the system  10  that further comprises a consolidated main body  61 , having a plurality of input leads  62 ,  63  and  64 , a user interface  65 , and a dedicated display  66  that are connected to an internal controller  70 . 
     The main body  61  can include any number of different shapes and sizes and can be constructed from any number of different materials suitable for encompassing each of the internal elements. In one preferred embodiment, the main body  61  can be constructed from lightweight injection molded plastic having a plurality of internal connectors (not shown) for securely housing and positioning each of the device elements. Of course, any number of other known construction materials such as PVC, metals and composites, for example, are also contemplated. 
     The input leads  62 ,  63  and  64  can each include any type of materials suitable for transmitting electronic signals. Each of the leads can also include connectors/adaptors along the ends so as to mate with or connect to a secondary device. These connectors can include, for example, various shaft-type plug connectors (e.g., banana plug), and/or compression fittings such as alligator clips, for example. In one embodiment, leads  62 ,  63  and  64  can incorporate identical components and can be used in an identical manner to leads  12 ,  13  and  7 , respectively described above. 
     The user interface  65  can function to accept user inputs and/or to provide operating information to a device user. In various embodiments, the user interface can include, comprise or control the illustrated buttons and switches that are connected to the internal controller so as to activate various programmatic functions. In one embodiment, the user interface device can also include or control one or more communication ports such as a Universal Serial Bus or micro-USB, for example, in order to send and receive information with another device via a direct communication link. 
     The display unit  66  can include any device capable of presenting information in a digital format to a user via a screen. Several nonlimiting examples include LCD displays, LED displays, electro-luminescent displays and the like. In various embodiments, the display unit  66  can also include a Graphic User Interface (GUI) capable of performing two-way communication with a device user so as to also function as the user interface  65 . 
     The internal controller  70  can be communicatively linked to each of the input leads  62 ,  63  and  64 , the user interface  65  and the display unit  66 . In the preferred embodiment, the internal controller can include identical components as the controller  20  described above, and can function the same manner described above when connected to the pressure sensor  4  and an engine cylinder, except the signals that would have been sent to the external display unit  6  shown above at  FIGS. 4 and 5  are instead sent to the dedicated display unit  66 . 
     Accordingly, the above-described device and method allow a vehicular technician to quickly and easily identify anomalies of individual fuel injectors within a vehicle engine, in a manner that does not require each injector to be removed and replaced or bench tested. 
     Although described above for use with dynamic GDI high pressure fuel system testing, the inventive concepts are not so limiting. Indeed, as vehicle technology continues to evolve, an ever-increasing number of vehicle data sensors are using serial data outputs which can be directly decoded and analyzed using the presently described device  10 . Several nonlimiting examples of engaging serial data engine sensors other uses include, but are not limited to: Ambient temperature, intake air temperature, manifold pressure, barometric pressure, mass air flow, engine coolant temperature, engine oil pressure, engine oil temperature, fuel pressure, fuel temperature, throttle position, vehicle speed, wheel speed, camshaft position, crankshaft position, variable valve lift position, and variable displacement, among others, for example. 
     As described herein, one or more elements of the fuel injector interface device  10  can be secured together utilizing any number of known attachment means such as, for example, screws, glue, compression fittings and welds, among others. Moreover, although the above embodiments have been described as including separate individual elements, the inventive concepts disclosed herein are not so limiting. To this end, one of skill in the art will recognize that one or more individually identified elements may be formed together as one or more continuous elements, either through manufacturing processes, such as welding, casting, or molding, or through the use of a singular piece of material milled or machined with the aforementioned components forming identifiable sections thereof. 
     As to a further description of the manner and use of the present invention, the same should be apparent from the above description. Accordingly, no further discussion relating to the manner of usage and operation will be provided. 
     The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. Likewise, the term “consisting” shall be used to describe only those components identified. In each instance where a device comprises certain elements, it will inherently consist of each of those identified elements as well. 
     The corresponding structures, materials, acts, and equivalents of all means or step plus function elements in the claims below are intended to include any structure, material, or act for performing the function in combination with other claimed elements as specifically claimed. The description of the present invention has been presented for purposes of illustration and description but is not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the invention. The embodiment was chosen and described in order to best explain the principles of the invention and the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated.