Distributed architecture ignition system

Abstract

Systems and methods for controlling an ignition system. The ignition coil assembly has an ignition transformer with a primary winding and a secondary winding and a local control unit. The spark device is connected with the secondary winding of the ignition transformer. The local control unit is adapted to adjust an ignition timing of the ignition transformer to generate a spark at the spark device to ignite a fuel-air mixture in the engine cylinder. The central control unit is in electronic communication with the local control unit to monitor the ignition transformer.

Description

Technical Field

[0001] The present teachings relate generally to power electronics and, more particularly, to ignition systems that may be used in internal combustion engines. Background Art

[0002] Generally speaking, as will be appreciated by those skilled in the art, an ignition system generates a high voltage that is sent to a spark plug to generate a spark. The spark in turn ignites the fuel-air mixture in the combustion chamber of the engine to drive the engine. An ignition coil (also known as an ignition transformer) typically generates a high voltage. U.S. Patent No. 7,401,603, entitled "High Voltage Capacitor Discharge Ignition with Enhanced Trigger Pulse," discloses an ignition system, and the entire contents of which are incorporated herein by reference.

[0003] As will be appreciated by those skilled in the art, known ignition systems employ centralized control, meaning that they have a single control unit that can be used with multiple ignition transformers. However, as discussed below, benefits may be realized by using a distributed control system.

[0004] Therefore, it would be beneficial to provide alternative systems and methods for distributed architecture ignition systems. Summary of the invention

[0005] The present embodiments address the needs set forth herein as well as further and other needs and advantages, and these embodiments illustrate the solutions and advantages described below.

[0006] One embodiment of a system according to the present teachings includes, but is not limited to, an ignition system having a central control unit. An ignition coil assembly (or assemblies) has an ignition transformer having a primary winding and a secondary winding and a local control unit. The local control unit is adapted to adjust the ignition timing of the ignition transformer to generate a spark at a spark device (e.g., connected in series with the secondary winding of the ignition transformer) to ignite a fuel-air mixture in an engine cylinder. The central control unit electronically communicates with the local control unit to monitor the ignition transformer.

[0007] In one embodiment, the local control unit steps up the final primary drive within the coil assembly to provide a higher primary drive voltage when the central control unit uses a low voltage cable.

[0008] In one embodiment, the central control unit provides a voltage of 50V or less to the ignition coil assembly, and the ignition coil assembly boosts the final primary drive to 400V or more.

[0009] In one embodiment, the ignition coil assembly includes a power source for stepping up the final primary drive in the coil assembly.

[0010] In one embodiment, the central control unit electronically communicates with the local control units via twisted pair cables.

[0011] In one embodiment, the twisted pair cable comprises an Ethernet cable.

[0012] In one embodiment, the local control unit increases the voltage of the primary drive input within the coil assembly.

[0013] In one embodiment, the spark device comprises a spark plug.

[0014] In one embodiment, the system has one or more additional ignition coil assemblies. Each of the one or more additional ignition coil assemblies has a control unit adapted to adjust the ignition timing of the associated ignition transformer.

[0015] In one embodiment, the ignition coil assembly includes at least one sensor such that the local control unit adjusts the ignition timing based on a measurement sensed by the sensor. The central control unit is in electronic communication with the local control unit via a twisted pair cable.

[0016] One embodiment of a method according to the present teachings includes, but is not limited to, a method for controlling an ignition system. A central control unit is provided. An ignition coil assembly is provided, the ignition coil assembly having an ignition transformer and a local control unit, the ignition transformer having a primary winding and a secondary winding. The local control unit is used to adjust the ignition timing of the ignition transformer to generate a spark at a spark device (e.g., connected to the secondary winding of the ignition transformer) to ignite a fuel-air mixture in an engine cylinder.

[0017] In one embodiment, a central control unit is used to monitor the local control units.

[0018] One embodiment of an ignition coil assembly according to the present teachings includes, but is not limited to, an ignition transformer having a primary winding and a secondary winding and a control unit adapted to adjust the ignition timing of the ignition transformer to generate a spark at a spark device to ignite a fuel-air mixture in an engine cylinder, the control unit adapted to electronically communicate with a central control unit that monitors the ignition transformer.

[0019] In one embodiment, the ignition coil assembly includes a power supply for stepping up the final primary drive voltage in the coil assembly to provide a higher primary drive voltage when the central control unit uses a low voltage cable.

[0020] In one embodiment, the ignition coil assembly includes at least one measurement value such that the local control unit adjusts the ignition timing based on the at least one measurement value.

[0021] In one embodiment, an ignition coil assembly includes at least one sensor for sensing at least one measurement value.

[0022] In one embodiment, the at least one measurement includes position data of a crankshaft of the engine.

[0023] One embodiment of an engine ignition system according to the present teachings includes, but is not limited to, an engine having a plurality of cylinders, each of the plurality of cylinders having an associated component according to the present teachings. A central control unit electronically communicates with each associated component via a twisted pair cable.

[0024] In one embodiment, the central control unit receives a diagnostic measurement of a first associated component and modifies operation of at least a second associated component based at least in part on the diagnostic measurement.

[0025] In one embodiment, the ignition coil assembly includes at least one measurement (e.g., may include a sensor or be received from another source (e.g., a sensor on the cylinder), etc.), so that the control unit adjusts the ignition timing based on the measurement. The central control unit electronically communicates with the ignition coil assembly control unit via a twisted pair cable.

[0026] Other embodiments of the system and method are described in detail below and are also a part of the present teachings.

[0027] For a better understanding of the present embodiments, as well as other and further aspects of the present embodiments, reference should be made to the accompanying drawings and detailed description, and the scope thereof will be pointed out in the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is an illustration of one embodiment of a system according to the present teachings.

[0029] Figure 2 is an illustration of another embodiment of a system according to the present teachings.

[0030] Figure 3 yes Figure 1 and Figure 2 An embodiment of the invention is incorporated into an illustration of an engine ignition control. DETAILED DESCRIPTION

[0031] The present teaching will be described more fully below with reference to the accompanying drawings, in which the present embodiment is shown. The following description is for illustrative purposes only, and the present teaching should not be limited to these embodiments. Any computer configuration and architecture that meets the speed and interface requirements described herein may be suitable for implementing the system and method of the present embodiment.

[0032] In compliance with the statute, the present teachings describe structural and methodological features in more or less specific language. However, it should be understood that the present teachings are not limited to the specific features shown and described, since the systems and methods disclosed herein include preferred forms of putting the present teachings into practice.

[0033] For purposes of explanation rather than limitation, specific details are set forth, such as particular architectures, interfaces, techniques, etc., in order to provide a thorough understanding. In other instances, detailed descriptions of well-known devices, circuits, and methods are omitted so as not to obscure the description with unnecessary detail.

[0034] A "computing system" may provide functionality for the present teachings. A computing system may include software executing on a computer-readable medium that may be logically (but not necessarily physically) identifiable for a particular function (e.g., a functional module). A computing system may include any number of computers / processors that may communicate with each other over a network. A computing system may be in electronic communication with a data store (e.g., a database) that stores control and data information. The form of a computer-readable medium may include, but is not limited to, a disk, a hard drive, a random access memory, a programmable read-only memory, or any other medium that a computer can read.

[0035] Generally, unless otherwise expressly defined herein, all terms used in the claims should be interpreted according to their ordinary meaning in the technical field. Unless otherwise expressly stated, all references to elements, devices, parts, devices, steps, etc. should be publicly interpreted as referring to at least one instance of elements, devices, parts, steps, etc. Unless expressly stated, the steps of any method disclosed herein do not have to be performed in the exact order disclosed. The use of "first", "second", etc. for different features / components of the present disclosure is intended only to distinguish these features / components from other similar features / components, rather than to give these features / components any order or ranking.

[0036] To assist the Patent Office and any reader of patents issuing from this application in understanding the appended claims, it is noted that unless the phrase “means for” or “step for” is expressly used in a particular claim, no claim or claim element is intended to invoke 35 U.S.C. § 112(f).

[0037] Numerical ranges expressed as endpoints include all numbers within that range (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, 5, etc.) When a value range for a particular value is "greater than," "less than," etc., that value is included in that range.

[0038] Any directions mentioned herein, such as "top", "bottom", "left", "right", "upper", "lower", "above", "below", and other directions and orientations, are described herein with reference to the accompanying drawings for clarity and are not intended to limit the actual device or system or the use of the device or system. Many of the devices, articles, or systems described herein can be used in multiple directions and orientations.

[0039] Any citation to a reference in this disclosure or during its review is made with due care. No citation (whether in an information disclosure statement or otherwise) should be construed as an admission that the cited reference constitutes prior art or is from an area similar to or directly applicable to the present teachings.

[0040] The present teachings include a distributed architecture ignition system. This can be based on enhanced capacitive discharge technology where the ignition coil assembly is integrated upward with the control and power electronics, but is not limited to this. This configuration provides many benefits including, but is not limited to, improved packaging, signal processing, control, and miniaturization.

[0041] In one embodiment, each of the one or more ignition coil assemblies (e.g., ignition transformer and electronics) has its own control unit. A central control unit (e.g., ECU) can communicate electronically with these "smart" ignition coils. The connection can be provided using a communication cable such as, but not limited to, a 4-pair CAT5e / 6 cable (e.g., Ethernet cable). In this way, the primary drive of the ignition coil can be placed "local" to the coil, but can be monitored by the central control unit.

[0042] Having a local control unit (also referred to as a distributed control unit, etc.) provides many new and improved features over existing systems. These features include a distributed architecture, local primary drive, local signal processing, local decision making, etc. It also provides the ability to integrate additional electronics with the ignition coil. For example, sensors such as temperature sensors and acceleration sensors can be added, but are not limited to this.

[0043] Those skilled in the art will appreciate that various sensors may be employed locally in the coil to measure such things as temperature (e.g., inside the coil) and acceleration (e.g., again, inside the coil). The sensors may also serve as a "signal processing and digitization" point. For example, this may allow a user to connect cylinder-based sensors (e.g., in-cylinder pressure diagnostics, etc.) to the coil electronics rather than having a wired connection to a central control unit, but is not limited to this.

[0044] Reference now Figure 1, which shows a diagram of one embodiment of a system 100 according to the present teachings. A central control unit 102 (e.g., an electronic control unit or ECU) can provide a central connection point for the ignition system 100. Although central control units are known in the art, as will be appreciated by those skilled in the art, a central control unit 102 according to the present teachings can provide supervisory control logic (e.g., monitoring, high-level control, providing data and ignition strategies, etc.) for distributed control units. The central control unit 102 can also provide some or all of the power supply (e.g., the first stage), but is not limited thereto.

[0045] Each ignition coil assembly 104 may have its own control logic, including a (distributed / local) control unit. In this way, at least some control and / or monitoring of the ignition transformer may be performed locally at the ignition transformer.

[0046] The ignition coil assembly 104 may include functions such as, but not limited to, a power supply (eg, second stage), a capacitive discharge ignition driver, an ignition transformer, and an engine diagnostic interface. Those skilled in the art appreciate the various functions that may be incorporated into the ignition coil assembly 104 according to the present teachings.

[0047] Each ignition coil assembly 104 can communicate with the central control unit 102 via one or more communication links 106 (e.g., bus, cable, etc.). In one embodiment, the link / bus includes a standard twisted pair cable (e.g., Category 5 or Category 6), but as will be appreciated by those skilled in the art, any wire / cable that can meet the communication requirements between the central control unit and the distributed control units can be used.

[0048] Placing the control electronics local to the ignition coil has several benefits. This allows each coil to effectively operate independently or semi-independently and respond quickly to local conditions for the specific application.

[0049] One benefit of the present teachings includes minimizing cabling between individual coils (eg, cylinders) and a central control module. For example, because signals can be processed locally at the coil, fewer conductors are required for coordination and serial communication with the central unit.

[0050] Another benefit is that the control electronics within the coil allow the electrical paths in both the power supply and the measurement circuits to be shorter and more controlled. This reduces effects such as, but not limited to, undesirable energy transfer (e.g., losses W = (IR)I or "I2R losses"), stray capacitance, etc.

[0051] Further, another benefit of the distributed architecture is that it can provide high primary drive voltages while retaining low voltage cables. Due to practical limitations of cable connection insulation levels, personnel safety, etc., typical capacitive discharge (CDI) ignition coil primary drive voltages can be in the range of 100-400VDC (pulse). However, as those skilled in the art will appreciate, higher primary drive voltages can be advantageous for lower current switching, fewer magnetic circuits, etc. By distributing a lower voltage (e.g., 48VAC in one example) and boosting it locally within the coil assembly to the final primary drive, a higher primary drive voltage can be achieved while retaining low voltage cables. Therefore, the present teachings can provide higher voltages than those in known systems.

[0052] Due to limitations of conventional wiring practices, voltages much greater than 400V are impractical (e.g., three-phase 480VAC may be the highest voltage that electricians typically encounter). However, using the present teachings, it is possible to distribute low voltages and charge capacitors to higher voltages, such as 600-900VDC, or even 1200-1800VDC, but not limited to. The benefit of distributing low voltages is that the distributed low voltages (e.g., less than 100V, less than 75V, less than 50V, less than 48V, etc.) remain "touch safe" no matter how much the primary voltage is boosted to (e.g., 400VDC, 500VDC, 600VDC, 700VDC, 800VDC, 900VDC, 1000VDC, 1100VDC, 1200VDC, 1300VDC, 1400VDC, 1500VDC, 1600VDC, 1700VDC, 1800VDC, etc.). As an example, 48V is safe to touch, whereas even 200VDC can be dangerous.

[0053] Voltage boost is known in the art, and as an example, it can be provided in the ignition coil assembly by an AC-DC or DC-DC power supply. In another example, a supplementary transformer and / or diode can be used, but is not limited thereto.

[0054] refer to Figure 2 , which shows a diagram of another embodiment of a system 200 according to the present teachings. As shown, a central control unit 202 (e.g., ECU, CPU, etc.) is in electronic communication with at least one ignition coil assembly 204. In this example, communication is carried out via a twisted pair cable 206, however, as will be appreciated by those skilled in the art, any cable connection that can meet the communication requirements (e.g., wireless control and monitoring) may be used.

[0055] Although a single ignition coil assembly 204 is shown and may be referred to herein, many ignition coil assemblies 204 may be connected to the central control unit 202. As will be appreciated by those skilled in the art, the disclosed functionality applies when multiple ignition coil assemblies 204 are present (e.g., one or more per engine cylinder).

[0056] The central control unit 202 may have a microcontroller 208 (e.g., processor, memory, input / output, etc.). The microcontroller 208 may control and monitor the operation of one or more ignition coil assemblies 204. In a preferred embodiment, the central control unit 202 may have supervisory monitoring and control capabilities because at least some functions have been allocated to the ignition coil assemblies 204 in accordance with the present teachings.

[0057] Those skilled in the art will appreciate that various supervisory monitoring and control capabilities may be incorporated into the present teachings. For example, these capabilities may include reading position data of the engine crankshaft and instructing the coil to fire at the appropriate time. In another example, these capabilities may include monitoring diagnostic data from a cylinder and adjusting one or more other cylinders in response, but are not limited to this. Diagnostic data may be used to monitor engine performance, such as engine stability or speed / torque fluctuations. Diagnostic data may include data from the cylinder to be analyzed (e.g., the voltage of the left engine bank is higher than the voltage of the right engine bank, etc.), but are not limited to this.

[0058] In one embodiment, the central control unit 202 may provide a low voltage power supply 210 (e.g., a touch safe voltage, 48V, etc.) to the ignition coil assembly 204. The central control unit 202 may have an electronic communication interface 212 for communicating with the ignition coil assembly 204 (e.g., receiving and sending communication signals, etc.). The central control unit 202 may provide control signals 214 for controlling and / or monitoring various aspects of the ignition coil assembly 204. It should be understood that the central control unit 202 may have various functions implemented in hardware and / or software for interacting with the ignition coil assembly 204, as understood by those skilled in the art.

[0059] Each ignition coil assembly 204 may have a microcontroller 216 (e.g., processor, memory, input / output, etc.). In this way, at least some control operations may be performed "locally" to the ignition coil assembly 204. As will be appreciated by those skilled in the art, this may include spark generation (e.g., a pulsed bit stream delivered to a switch), diagnostic measurements (e.g., primary and / or secondary current and voltage), etc.

[0060] The ignition coil assembly 204 may have a primary drive power supply 218. The ignition coil assembly 204 may have an electronic communication interface 220 (e.g., for communicating with the central control unit 202, other ignition coil assemblies, etc.). The ignition coil assembly 204 may have an ignition transformer 222 and a driver (i.e., an "output stage" for controllable switching / ignition). The ignition coil assembly 204 may have an engine diagnostic signal 224. It should be understood that the ignition coil assembly 204 may have various functions implemented in hardware and / or software for interacting with other parts of the system (e.g., the central control unit 202), as well as for controlling the ignition transformer 222 (e.g., adjusting ignition timing, etc.), as understood by those skilled in the art.

[0061] refer to Figure 3 , which shows Figure 1 and Figure 2 302 , 302 ', 302 ''. Each component may send energy to a spark plug 308 , 308 ', 308 ''. As will be appreciated by those skilled in the art, the spark plug may in turn drive a crankshaft in an engine 310 (e.g., one or more spark plugs in each engine cylinder).

[0062] Although the present teachings have been described above in terms of specific embodiments, it should be understood that they are not limited to these disclosed embodiments. Those skilled in the art will recognize many modifications and other embodiments, which are intended to be and are covered by the present disclosure. As those skilled in the art will understand from the disclosures in this specification and the accompanying drawings, the scope of the present teachings should be intended to be determined by appropriate interpretation and construction of its legal equivalents.

Claims

1. An ignition system, comprising: An ignition coil assembly having: an ignition transformer having a primary winding and a secondary winding; a local control unit adapted to adjust the ignition timing of said ignition transformer to generate a spark at a spark device to ignite a fuel-air mixture in a cylinder of the engine; A central control unit is in electronic communication with the local control units to monitor the ignition transformer.

2. The system according to claim 1, wherein: The ignition coil assembly boosts the final primary drive voltage within the ignition coil assembly to provide a higher primary drive voltage when the central control unit uses a low voltage cable.

3. The system according to claim 2, wherein: The ignition coil assembly includes a power source for stepping up the final primary drive voltage.

4. The system according to claim 2, wherein: The central control unit provides a voltage of 50V or less to the ignition coil assembly, and the ignition coil assembly boosts the final primary drive voltage to 400V or more.

5. The system according to claim 1, wherein: The central control unit is in electronic communication with the local control units via twisted pair cables.

6. The system according to claim 5, wherein: The twisted pair cable comprises an Ethernet cable.

7. The system according to claim 1, wherein: The spark device includes a spark plug.

8. The system of claim 1, further comprising: one or more additional ignition coil assemblies; Each of the one or more additional ignition coil assemblies has a local control unit adapted to adjust the ignition timing of an associated ignition transformer.

9. An engine system comprising: engine; The ignition system according to claim 8; Each ignition coil assembly is caused to adjust the ignition timing of an associated ignition transformer to generate a spark at a spark device to ignite a fuel-air mixture in a cylinder of the engine.

10. The system of claim 1, wherein: The ignition coil assembly includes at least one measurement value, such that the local control unit adjusts the ignition timing based on the at least one measurement value; The central control unit is in electronic communication with the local control units via twisted pair cables.

11. A method for controlling an ignition system, comprising: An ignition coil assembly is provided, the ignition coil assembly having: an ignition transformer having a primary winding and a secondary winding; Local control unit; adjusting, using the local control unit, an ignition timing of the ignition transformer to generate a spark at a spark device to ignite a fuel-air mixture in a cylinder of an engine; The ignition transformer is monitored using a central control unit.

12. The method according to claim 11, wherein: The ignition coil assembly includes at least one measurement value, such that the local control unit adjusts the ignition timing based on the at least one measurement value; The central control unit is in electronic communication with the local control units via twisted pair cables.

13. An ignition coil assembly, comprising: an ignition transformer having a primary winding and a secondary winding; a local control unit adapted to adjust the ignition timing of said ignition transformer to generate a spark at a spark device to ignite a fuel-air mixture in a cylinder of the engine; The local control unit is adapted to be in electronic communication with a central control unit monitoring the ignition transformer.

14. The assembly of claim 13, wherein: The ignition coil assembly includes a power supply for stepping up the final primary drive voltage in the ignition coil assembly so as to provide a higher primary drive voltage when the central control unit uses a low voltage cable.

15. The assembly of claim 13, wherein: The ignition coil assembly includes at least one measurement value such that the local control unit adjusts ignition timing based on the at least one measurement value.

16. The assembly of claim 15, wherein: The ignition coil assembly includes at least one sensor for sensing the at least one measurement value.

17. The assembly of claim 15, wherein: The at least one measurement includes position data of a crankshaft of the engine.

18. An engine ignition system, comprising: an engine having a plurality of cylinders; Each of the plurality of cylinders has an associated assembly according to claim 13; A central control unit that communicates electronically with each associated component via twisted pair cables.

19. The system of claim 18, wherein: The central control unit receives diagnostic measurements of a first associated component and modifies operation of at least a second associated component based at least in part on the diagnostic measurements.

20. The system of claim 18, wherein: a local control unit increasing a voltage of a primary drive within one of said associated components; The central control unit is in electronic communication with the local control units via twisted pair cables.

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