阅读说明：本技术 用于在高温火花塞延伸件中的独特材料和几何形状的方法和系统 (Methods and systems for unique materials and geometries in high temperature spark plug extensions ) 是由 马克·诺塔尔弗朗切斯科 罗伯特·普拉罗 蒙特·韦格纳 于 2018-03-23 设计创作，主要内容包括：一种用于在高温火花塞延伸件中的独特材料和几何形状的方法和系统,可包括火花塞延伸件,其具有围封在液晶聚合物中的导电核心,其中导电核心的相对端部未围封在液晶聚合物中。线圈可直接耦接到火花塞延伸件。火花塞延伸件和线圈可在导电核心的相对端部的第一端部处包括螺纹,以将线圈直接耦接到火花塞延伸件。导电核心的相对端部的第一端部处可包括提供与线圈密封的O形环。火花塞延伸件可包括绝缘线,其远离火花塞延伸件地耦接到线圈,该绝缘线从导电核心的一个端部延伸。(A method and system for unique materials and geometries in a high temperature spark plug extension may include a spark plug extension having a conductive core enclosed in a liquid crystal polymer, wherein opposite ends of the conductive core are not enclosed in the liquid crystal polymer. The coil may be directly coupled to the spark plug extension. The spark plug extension and the coil may include threads at a first end of the electrically conductive core at opposite ends to directly couple the coil to the spark plug extension. An O-ring may be included at a first end of the opposite end of the conductive core to provide a seal with the coil. The spark plug extension may include an insulated wire coupled to the coil distal from the spark plug extension, the insulated wire extending from one end of the conductive core.)

1. A system for engine ignition, the system comprising:

a spark plug extension comprising a conductive core enclosed in a liquid crystal polymer, wherein opposing ends of the conductive core are not enclosed in the liquid crystal polymer.

2. The system of claim 1, wherein a coil is directly coupled to the spark plug extension.

3. The system of claim 2, wherein the spark plug extension and the coil include threads, the spark plug extension including threads at a first end of the opposing ends of the conductive core to directly couple the coil to the spark plug extension.

4. The system of claim 3, wherein at the first end of the opposing ends of the conductive core comprises providing a seal with the coil of one or more of: o-rings, grommets, and washers.

5. The system of claim 1, wherein the spark plug extension includes an insulated wire coupled to a coil remote from the spark plug extension, the insulated wire extending from one end of the conductive core.

6. The system of claim 1, wherein the conductive core includes a tapered end at one of the opposing ends to make electrical contact with a spark plug coupled to the spark plug extension.

7. The system of claim 6, wherein the tapered end comprises a spring.

8. The system of claim 1, wherein a portion of the liquid crystal polymer extends beyond a second end of the opposing ends of the conductive core to enclose a portion of a spark plug coupled to the spark plug extension.

9. The system of claim 8, wherein the portion of the injected liquid crystal polymer extending beyond the second end of the opposite end of the conductive core comprises an O-ring providing a seal with the spark plug.

10. The system of claim 1, wherein the liquid crystal polymer exhibits an increased dielectric strength with increasing temperature at engine operating temperatures.

11. The system of claim 1, wherein the spark plug extension exhibits a reduced voltage drop with increasing temperature at engine operating temperatures.

12. The system of claim 1, wherein the liquid crystal polymer comprises an injection molded liquid crystal polymer.

13. The system of claim 12, wherein the injection molded liquid crystal polymer comprises Xydar.

14. The system of claim 1, wherein the conductive core comprises an insulated metal wire.

15. The system of claim 1, wherein the liquid crystal polymer comprises a glass reinforcement.

16. The system of claim 1, wherein the spark plug extension comprises a processed liquid crystal polymer.

17. A method for engine ignition, the method comprising:

including a spark plug extension comprising a conductive core enclosed in a liquid crystal polymer, wherein opposite ends of the conductive core are not enclosed in the liquid crystal polymer:

receiving a high voltage electrical signal at a first one of the opposing ends of the conductive core; and

communicating the high voltage electrical signal to a second one of the opposing ends of the conductive core.

18. The method of claim 17, comprising the steps of: a coil is directly coupled to the spark plug extension.

19. The method of claim 18, wherein the spark plug extension and the coil include threads, the spark plug extension including threads at the first end of the opposing end of the conductive core to directly couple the coil to the spark plug extension.

20. The method of claim 18, wherein at the first end of the opposing ends of the conductive core comprises providing a seal with the coil of one or more of: o-rings, grommets, and washers.

21. The method of claim 17, wherein the spark plug extension includes an insulated wire operably coupled to a coil remote from the spark plug extension, the insulated wire extending from one end of the conductive core.

22. The method of claim 17, wherein the conductive core includes a tapered end at one of the opposing ends to make electrical contact with a spark plug coupled to the spark plug extension.

23. The method of claim 22, wherein the tapered end comprises a spring.

24. The method of claim 17, wherein a portion of the liquid crystal polymer extends beyond a second end of the opposite end of the conductive core to enclose a portion of a spark plug coupled to the spark plug extension.

25. The method of claim 24, wherein the portion of the liquid crystal polymer extending beyond the second end of the opposite end of the conductive core comprises one or more of the following to provide a seal with the spark plug: o-rings, grommets, and washers.

26. The method of claim 17, wherein the spark plug extension exhibits a reduced voltage drop with increasing temperature at engine operating temperatures.

27. The method of claim 17, wherein the liquid crystal polymer comprises an injection molded liquid crystal polymer.

28. The method of claim 27, wherein the injection molded liquid crystal polymer comprises Xydar.

29. The method of claim 17, wherein the conductive core comprises an insulated metal wire.

30. The method of claim 17, wherein the injection molded liquid crystal polymer comprises a glass reinforcement material.

31. The method of claim 30, wherein the spark plug extension comprises a processed liquid crystal polymer.

32. A system for engine ignition, comprising:

a spark plug extension comprising an electrically conductive core enclosed in a liquid crystal polymer, wherein opposing ends of the electrically conductive core are not enclosed in the liquid crystal polymer, wherein a first of the opposing ends is operable to make electrical contact with a coil and a second of the opposing ends is operable to make electrical contact with a spark plug.

33. The system of claim 30, wherein the spark plug extension exhibits a reduced voltage drop with increasing temperature at engine operating temperatures.

34. The system of claim 30, wherein the liquid crystal polymer comprises an injection molded liquid crystal polymer.

35. The system of claim 32, wherein the injection molded liquid crystal polymer comprises Xydar.

36. The system of claim 30, wherein the liquid crystal polymer comprises a glass reinforcement.

Technical Field

Certain embodiments of the present disclosure relate to engine ignition components. More specifically, certain embodiments of the present disclosure relate to methods and systems for unique materials and geometries in high temperature spark plug extensions.

Background

Existing devices that provide ignition energy to engine spark plugs are expensive and suffer from reliability problems in the high temperature and corrosive environment of the engine. In the case where the engine head is too high to enable a simple high voltage wire to be coupled directly to the spark plug (e.g., typically for large industrial machines), a spark plug extension may be used to provide a signal from the high voltage coil to the spark plug.

Further limitations and disadvantages of conventional and traditional approaches will become apparent to one of skill in the art, through comparison of such systems with the present disclosure as set forth in the remainder of the present application with reference to the drawings.

Disclosure of Invention

A system and/or method for unique materials and geometries in a high temperature spark plug extension, substantially as shown in and/or described in connection with at least one of the figures, as set forth more completely in the claims.

These and various other advantages, aspects and novel features of the disclosure, as well as details of illustrated embodiments thereof, will be more fully understood from the following description and drawings.

Drawings

FIG. 1 illustrates a cross-sectional view of an exemplary ignition system of an internal combustion engine that may be used in various embodiments according to the present disclosure.

Fig. 2 illustrates a high voltage wire according to an exemplary embodiment of the present disclosure.

FIG. 3 illustrates an example spark plug extension with a mounted coil according to an example embodiment of this disclosure.

FIG. 4 illustrates a graph of delivered voltage versus temperature for a spark plug extension according to an exemplary embodiment of the present disclosure.

DETAILED DESCRIPTION OF EMBODIMENT (S) OF INVENTION

As utilized herein, "and/or" means any one or more of the listed items connected with "and/or". For example, "x and/or y" means any element of the three-element set { (x), (y), (x, y) }. Similarly, "x, y, and/or z" means any element of the seven element set { (x), (y), (z), (x, y), (x, z), (y, z), (x, y, z) }. As utilized herein, the term "module" refers to functionality that may be performed in hardware, software, firmware, or any combination of one or more thereof. As utilized herein, the term "exemplary" is intended to be used as a non-limiting example, illustration, or description.

FIG. 1 illustrates a cross-sectional view of an exemplary ignition system of an internal combustion engine that may be used in various embodiments according to the present disclosure. Referring to fig. 1, there is shown an ignition system 100 including a high voltage ignition coil 101, a spark plug extension 103, a spark plug 105, and a cylinder 107, and a cylinder head 109. The cylinder head 109 includes structure at the top of the cylinder 107 to help form a combustion chamber along the cylinder and piston.

The ignition coil 101 may include a primary coil, a secondary coil, and a core, wherein the number of turns of the primary and secondary coils is configured to convert a low voltage to a high voltage (e.g., several thousand volts) required to generate a spark in the spark plug 105. In the example shown in fig. 1, the ignition coil 101 is located within the cylinder head 109 to minimize the distance that the high voltage signal needs to be transferred, while other designs may have a coil external to the cylinder head 109 with a high voltage line coupling the remote coil to the spark plug extension 103.

The spark plug extension 103 includes an insulator 103B that surrounds a conductive central path (e.g., a high voltage conductive rod 103A) to provide high voltage to the spark plug 105. For large bore engines, a rigid, accessible insulated conductor is required to deliver ignition energy to the high voltage terminals of spark plug 105, which can withstand significant amounts of heat while also withstanding dielectric strength. It would be desirable to have a cost effective rigid insulator capable of delivering high voltage pulses to spark plug 105 in environments up to and exceeding 200 c to enable spark generation. Further, spark plug extension 103 should be mechanically and electrically durable due to the vibration, temperature, and chemical aspects of the engine environment. One or more O-rings may be integrated into spark plug extension 103 to create a sealed connection with spark plug 105 and/or coil 101.

The amount of voltage delivered to the spark plug at elevated temperatures is a performance parameter of the spark plug extension. The voltage delivered to the spark plug at varying temperatures may be measured using a simulated engine environment. Furthermore, the ability to maintain the proper dielectric properties of the spark plug extension to still deliver a high voltage signal after many hours of use is an important parameter of the spark plug extension.

Commonly used materials for spark plug extensions include polyimide-based plastics. However, over time and with increasing temperature, the dielectric strength of these materials decreases, greatly reducing their insulating properties. In an exemplary aspect, a liquid crystal polymer may be used to form the spark plug extension 103. In an exemplary embodiment, the liquid crystal polymer comprises an injection molded liquid crystal polymer. The fully aromatic structure of the liquid crystal polymer provides fewer charge carriers than the C ═ O bonds of the polyimide. In addition, glass reinforced materials of liquid crystal polymers provide excellent dielectric properties even in harsh engine environments. This factor is important because the dielectric strength of the material determines the maximum open circuit voltage that the insulator can withstand before failing. Further, it has been shown that the disclosed spark plug extension including a liquid crystal polymer has improved dielectric strength with temperature, and has excellent corrosion resistance and abrasion resistance.

An exemplary injection molded liquid crystal polymer is Xydar, which is a glass reinforced injection molded polymer and exhibits good chemical resistance, formability, and high stiffness. Typically, the resistance of the material is 1 × 10¹⁶Omega-cm, and the dielectric strength is 39 kV/mm.

Further, forming the spark plug extension from a liquid crystal polymer enables the use of injection molding, and thus can be cost effectively manufactured by injecting the liquid crystal polymer into a mold structure having the liquid crystal polymer surrounding a high voltage rod (which solidifies into a solid spark plug extension component) to form the spark plug extension. At high temperatures, the resulting structure retains its dielectric capability and even exhibits increased dielectric strength with temperature. An exemplary injection molded liquid crystal polymer is glass reinforced, thermally stable polyphthalamide, which exhibits high thermal deflection temperature, high flexural modulus, low moisture absorption, and high tensile strength.

Fig. 2 shows a high voltage conductor according to a further exemplary embodiment of the present disclosure. Referring to fig. 2, there is shown a conductor 200 comprising an insulated wire 201 and an extension 203. Unlike the case of being mounted on an extension, the lead 200 may be used in conjunction with a remote coil (such as the ignition coil 101 shown in fig. 1 mounted directly on the spark plug extension 103). The extension 203 may include a high voltage conductive rod in a dielectric material to provide a high voltage to the spark plug without shorting adjacent conductive structures. By utilizing a remote coil, a high voltage is present along both the insulated wire 201 and the extension 203.

In an exemplary aspect, the extension 203 may comprise an injection molded liquid crystal polymer to enable high temperature dielectric capabilities in harsh engine environments. Remotely mounting one or more coils may provide advantages such as ease of maintenance or reduction in the number of coils required without the need to mount a coil at each spark plug. In further exemplary aspects, the extension 203 may include an insulated wire in a liquid crystal polymer and a wire extending to a remote coil.

FIG. 3 illustrates an example spark plug extension with a mounted coil according to an example embodiment of this disclosure. Referring to fig. 3, a coil 301 and a spark plug extension 303 are shown, with the extension and coil shown in cross-section to illustrate internal components (such as a conductive core 303A in an insulator 303B surrounding the rod).

The coil 301 may be substantially similar to the coil 101 described with respect to fig. 1, and the coil may be coupled directly to the spark plug extension 303, as opposed to being coupled to a remote coil (such as the high voltage wire in fig. 2). Direct coupling to the extension reduces the distance necessary to carry the high voltage, reducing the length of high voltage compatible material required for the insulator.

The coil may include a pair of coil conductors 301A wound around a core (not shown), the coil including a primary winding and a secondary winding for receiving an input voltage and generating a high voltage output of sufficiently high voltage to generate a spark at an attached spark plug. Further, the coil 301 may include threads 301B for coupling to a spark plug extension 303.

The spark plug extension 303 includes an inner high voltage conductive core 303A embedded in an insulator 303B. The conductive core 303A includes a conductive material (such as a metal) that can withstand the high temperature and corrosive environment of the engine compartment (e.g., at the exposed ends). In further exemplary aspects, the conductive core 303A may comprise an insulated wire in an insulator 303B. The conductive core 303A may include a tapered end 303E that may be utilized to make contact with a spark plug coupled to the extension 303. The tapered end 303E may include a tapered spring or coil for providing a force against the spark plug, although the present disclosure is not so limited, other structures (e.g., such as a solid tapered tip) may also be utilized to make contact with the spark plug.

Insulator 303B comprises an insulating material that can provide electrical isolation for the high voltage provided by conductive core 303A. In addition, the insulator 303B should be able to withstand the corrosive environment and remain structurally and electrically intact when subjected to the intense vibrations often encountered in engines. In an exemplary aspect, the insulator 303B includes a liquid crystal polymer, such as glass reinforced thermally stable polyphthalamide. The use of a liquid crystal polymer enables injection molding of the spark plug extension 303. The end of the conductive core 303A may be exposed (i.e., not covered by the insulator 303B) and thus may provide electrical contact with the coil 301 and a spark plug, such as the spark plug 105 shown in fig. 1.

Further, the spark plug extension 303 may include: a threaded portion 303C for coupling to the coil thread 301B of the coil 301; and a seal 303D for providing a relatively sealed environment within the coil 301 when attached to the spark plug extension 303 to protect the electrical connection from the corrosive environment of the engine compartment. The seal 303D may include an O-ring, a grommet, a gasket, combinations thereof, or other types of sealing mechanisms. While the exemplary coil/extension connector shown in fig. 3 utilizes external threads on the extension 303 and internal threads on the coil 301, this is interchangeable where there may be internal threads on the collar of the extension 303 and external threads on the extension of the coil 301.

In an exemplary aspect, the spark plug extension 303 may be formed using a liquid crystal polymer. The fully aromatic structure of the liquid crystal polymer provides fewer charge carriers than the C ═ O bonds of the polyimide. In addition, glass reinforced materials of liquid crystal polymers provide excellent dielectric properties even in harsh engine environments. This factor is important because the dielectric strength of the material determines the maximum open circuit voltage that the insulator can withstand before failing. Liquid crystal polymers have demonstrated dielectric strengths of approximately 40kv/mm, a value higher than that of the cost effective materials used prior to spark plug extensions. Further, it has been shown that the spark plug extension has improved dielectric strength with temperature and has excellent corrosion resistance. For example, a liquid crystal polymer spark plug extension installed in an engine with a leaking spark plug gasket results in the formation of residue on the exterior of the spark plug extension, but does not result in any dielectric failure or increase voltage loss at the spark plug terminals.

The exemplary liquid crystal polymer used to fabricate spark plug extension 103 results in a four-fold increase in the voltage supplied to the spark plug compared to standard materials used in the present application, such as polyimide-based plastics. In further exemplary aspects, the liquid crystal polymer can be processed to form a finished extension, as opposed to injection molding.

FIG. 4 illustrates a graph of delivered voltage versus temperature for a spark plug extension according to an exemplary embodiment of the present disclosure. Referring to FIG. 4, a graph of voltage supplied to a spark plug in a simulated engine environment for five spark plug extensions including extensions of liquid crystal polymer and conventional materials (e.g., polyimide) is shown. The voltage loss or the supply voltage which decreases with increasing temperature is a measure for the dielectric strength of the material. For example, a high dielectric strength material will have a low voltage loss and continue to provide a high voltage as the temperature increases, while a low dielectric strength material will exhibit a high voltage loss and supply a lower voltage to the spark plug at a higher temperature.

Voltage loss tests were performed in evaluating the performance of liquid crystal polymer spark plug extensions, wherein measurements were made at 25 ℃ (room temperature), 120 ℃, and 150 ℃. Fig. 4 shows the delivered voltages measured for 5 different liquid crystal polymer spark plug extensions compared to an extension of conventional material.

As shown in fig. 4, when the temperature is increased from 25 ℃ to 120 ℃, the voltage drop is not significant for the liquid crystal polymer device, but is significant for the conventional device. Furthermore, for most of the liquid crystal polymer devices tested, the voltage supplied from 120 ℃ to 150 ℃ (i.e., the voltage supplied through the spark plug extension) was actually increased, which is a significant improvement over conventional devices that lose a significant amount of voltage over this temperature range.

Certain aspects of the present disclosure may be found in methods and systems for unique materials and geometries for spark plug extensions at high temperatures. Exemplary aspects of the present disclosure may include a spark plug extension including a conductive core enclosed in a liquid crystal polymer, with opposite ends of the conductive core not enclosed in the liquid crystal polymer. The coil may be directly coupled to the spark plug extension. The spark plug extension and the coil include threads, wherein the spark plug extension includes threads at a first end of the opposite end of the conductive core to directly couple the coil to the spark plug extension.

The conductive core includes one or more at a first end of the opposing ends: o-rings, grommets and gaskets that provide a seal with the coil. The spark plug extension may include an insulated wire remotely coupled from the spark plug extension to the coil, the insulated wire extending from an end of the conductive core. The conductive core may include a tapered end at one opposing end to make electrical contact with a spark plug coupled to the spark plug extension. The tapered end may include a spring. A portion of the liquid crystal polymer may extend beyond a second end of the opposite end of the conductive core to enclose a portion of the spark plug coupled to the spark plug extension.

The portion of the injected liquid crystal polymer at the second end that extends beyond the opposite end of the conductive core may include an O-ring that provides a seal to the spark plug. Liquid crystal polymers may exhibit increased dielectric strength at increased temperatures with engine operating temperatures.

The spark plug extension may exhibit a reduced voltage drop with increasing temperature as the engine operating temperature increases. The liquid crystal polymer may comprise an injection molded liquid crystal polymer. The injection molded liquid crystal polymer may comprise Xydar. The conductive core may comprise insulated metal wires and the liquid crystal polymer may comprise glass reinforcement. The spark plug extension may include a processed liquid crystal polymer.

While the disclosure has been described with reference to certain embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the scope of the disclosure. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the disclosure without departing from the scope thereof. Therefore, it is intended that the disclosure not be limited to the particular embodiments disclosed, but that the disclosure will include all embodiments falling within the scope of the appended claims.