US3012085A

US3012085A - Spark plug assembly

Info

Publication number: US3012085A
Application number: US793095A
Authority: US
Inventors: Harold D Regar
Original assignee: Individual
Current assignee: Individual
Priority date: 1959-02-13
Filing date: 1959-02-13
Publication date: 1961-12-05
Anticipated expiration: 1978-12-05

Description

United States Patent G 3,012,085 SPARK PLUG ASSEMBLY Harold D. Regar, Temple, Pa. (P.0. Box 495, Woodside Ave, Alsace Manor, Reading, Pa.) Filed Feb. 13, 1959, Ser. No. 793,095 1 Claim. (Cl. 123-169) This invention relates to improvements in internal combustion engines, and it more particularly relates to improvements in spark plug assemblies.

One of the problems which has heretofore never been adequately solved is that relating to proper combustion control and more particularly that relating to the relief of high torque combustion or what is known as detonation. Another problem is that relating to spark plug timing for obtaining a greater amount of fuel economy and smoother running conditions both when idling and at all other speeds.

It is one object of the present invention to overcome the above and other difficulties by providing a means for slowing down the burning rate of compressed gases without loss of power or improper heat control of the spark plug.

Another object of the present invention is to provide a means to cushion engine combustion in general at all speeds including the idling speed.

Another object of the present invention is to provide a means for greatly increasing fuel economy in internal combustion engines.

Another object of the present invention is to prevent spark plug fouling caused by piston oil pumping and to maintain the plugs clean burning and free from carbon deposits regardless of the severity of the oil pumping condition.

Other objects of the present invention are to provide an improved spark plug assembly, of the character described, that is easily and economically produced, which is sturdy in construction, and which is highly efiicient in operation.

With the above and related objects in view, this invention consists in the details of construction and combina tion of parts, as will be more fully understood from the following description, when read in conjunction with the accompanying drawing in which:

FIG. 1 is a side elevational view of a spark plug assembly embodying the present invention.

FIG. 2 is a partly sectional and partly elevational view taken generally on the line 2-2 of FIG. 1.

FIG. 3 is a cross-sectional view taken on line 33 of FIG. 2.

Referring in greater detail to the drawing wherein similar reference characters refer to similar parts, there is shown a spark plug assembly, generally designated 10, which comprises a spark plug 12, of the usual standard construction, and a pre-ignition chamber 14.

The spark plug 12 is provided with a threaded stem or extension 16 on which is mounted the usual electrodes 18, these electrodes 18 being at the lower end thereof.

The threaded stem 16 is engaged in a threaded bore 20 of the chamber 14. This bore 20 connects, at its lower end, directly with a tapered passage 22. The passage 22 is provided with its wider end at the top, this wider end forming an uninterrupted and continuous extension of bore 20 with no shoulders in between so that a smooth, continuous flow passage is provided. The narrower, bottom end of tapered passage 22 is also continuously extended into a straight vertical passage 24 with the elimination of any shoulders or other obstructions therebetween. The lower end of passage 24 is open and is defined by a gradually, outwardly curved inner lip 26. v

The upper part of chamber 14 is heXagonally-shaped on its outer surface, as at 28, to permit the use of an appro- 3,012,035 Patented Dec. 5, 1961 priate wrench or similar tool, while at its lower end, the chamber v14 is reduced to form a nipple portion 30 having external threads and defining the lower straight passage 24.

The nipple portion 30 is separated from the upper portion of the chamber 14 by an external shoulder 32, and bearing on this shoulder 32 is a copper ring 34 surrounding the upper end of nipple portion 30.

Although the chamber 14 is threadcdly engaged on the stem 16 of the spark plug, it is spaced from the upper portion of the spark plug by a sufiicient distance to accommodate a ring 36 of copper or copper alloy. This ring 36 is integral with an outwardly-inclined plate 38 of the same metal. The ring 36 is releasably clamped between the chamber 14 and the upper portion of the spark plug 12.

The nipple 30 is connected to the standard cylinder head of an internal combustion engine with the copper ring 34 engaged against the cylinder head. Since the standard cylinder head is cooled by a cooling fluid such as air or water, this cooling effect is transferred through the conductive copper ring 34 to the p re-ignition chamber 14 whereby the chamber 14 is maintained externally at approximately the same temperature as the cooled cylinder head. At the same time, the gas mixture which is pre-ignited in passage 22 and expands therein, flows down through the restricted passage 24 and then gradually expands at outwardly tapered lip 26 before it flows into the main combustion chamber of the engine cylinder. However, since there are no shoulders, bafiies or other obstructions to the flow between passage 22 and the main combustion chamber, there is a minimum of turbulence and therefore a minimum of heat generation on the walls of the chamber 14.

The combined eifects of the heat dissipation of the copper ring 34 and the diminution of turbulence within the chamber 14 results in comparatively cool operating conditions. In addition, for complete normal running temperature in a dry burning engine (when there is no oil pumping), the ring 36 is clamped between the spark plug 12 and the chamber 14 (as illustrated in the drawing). This ring, carrying the plate 38, aids heat dissipation since the plate 38 acts as an air-cooled fin.

If the engine is pumping oil, then the ring 36 may be removed and a ring such as ring 34 may be substituted. This substituted ring will then act as a heat conductor, thereby increasing the temperature at the area of the spark plug electrodes. This increased temperature will burn off carbon deposits keeping the spark plug electrodes clean. If the oil pumping is very severe, then the ring 36 is re placed by a conventional copper type collapsible spark plug gasket (not shown) since this will cause closer contact between the spark plug 12 and chamber 14. This gives even less cooling but the resultant hotter temperatures enable the spark plug electrodes to be more effectively burned clean. Nevertheless, even though such hotter temperatures are effected around the spark plug electrodes, the total heat absorption in the chamber '14 is effectively reduced because of the smooth flow conditions therein and because of the heat dissipation effects of ring 34.

Because of the slower burning conditions existing in the chamber 14, the spark timing can readily be advanced resulting in added fuel economy with standard gasoline. This is due to the fact that slow burning eliminates pings ing or detonation, (thereby providing smoother engine performance because the pressure stroke of the piston is sustained. In contrast, faster burning systems have detonation or flash burning at piston dead center point which tends to shorten pressure time. As a result, the engine operates roughly and inefi'iciently. To ameliorate such 3 conditions, the timing must be retarded in such engines, thereby resulting in low mileage or fuel inefiiciency.

Although this invention has been described in considerable detail, such description is intended as being illustrative rather than limiting, since the invention may be variously embodied, and the scope of the invention is to be determined as claimed.

Having thus set forth and disclosed the nature of this invention, what is claimed is:

A spark plug assembly comprising a spark plug having an externally threaded stem provided with electrodes at the lower end thereof, a pre-ignition chamber having an internally threaded bore, said spark plug stembeing threadedly engaged in said bore, a continuous, smooth, uninterrupted frusto-conical tapered passage extending continuously from one end of said threaded bore, the taper angle of said tapered passage to its axis being substantially 20, the wider end of said tapered passage being connected to said threaded bore, the diameter of said wider end being no greater than that of said threaded bore, a straight cylindrical passage of the same width as the narrower end of said tapered passage and continuously connected to said narrower end, the axial length of said tapered passage being at least equal to the axial length of said straight cylindrical passage, the diameter of said straight cylindrical passage being at least half that of said wide end of said tapered passage, a gradu- 5 ally widening internal lip at the free end of said straight passage which is opposite the end connected to said tapered passage, and a spark plug stem thread externally on said straight passage to releasably connect to a threaded spark plug aperture of an engine cylinder head of an 10 internal combustion engine.

References Cited in the file of this patent UNITED STATES PATENTS 1,357,661 Vail Nov. 2, 1920 15 1,392,364 Smith Oct. 4, 1921 1,495,215 Williams May 27, 1924 1,750,063 Sorg Mar. 11, 1930 2,236,762 Ottofy Apr. 1, 1941 2,238,852 Regar Apr. 15, 1941 20 2,702,537 Wright et al Feb. 22, 1955 FOREIGN PATENTS 216,391 Great Britain May 29, 1924